Here's the total of races won of 10km or more on the Women's World Cup not won by the three athletes above since 2011-12.Has she given an exact date? Be nice to go into a distance event with some degree of uncertainty. How many races of 10km + has anyone other than Johaug, Bjoergen or Kowalczyk won, where they were competing, in the last 15 years? Probably less than 10%.
Feb 2, 2013, Sochi - 15km skiathlon - Kristin Størmer Steira (believe reduced field so likely none of the above in action)
Dec 1, 2013, Kuusamo - 10km freestyle pursuit - Charlotte Kalla
Jan 1, 2014, Lenzerheide (Tour de Ski stage) - 10km classic mass start - Kerttu Niskanen (no Bjørgen or Kowalczyk, but definitely Johaug)
Jan 23, 2015, Rybinsk - 10km freestyle - Astrid Uhrenholdt Jacobsen (none of the three competing)
Jan 25, 2015, Rybinsk - 15km skiathlon - Martine Ek Hagen (none of the three competing)
Feb 15, 2015, Östersund - 10km freestyle - Charlotte Kalla
Jan 9, 2016, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Heidi Weng
Mar 5, 2016, Quebec (Ski Tour Canada stage) - 10km freestyle pursuit - Heidi Weng
Mar 11, 2016, Lake Louise (Ski Tour Canada stage) - 10km freestyle - Ingvild Flugstad Østberg
Mar 12, 2016, Canmore (Ski Tour Canada stage) - 10km classic pursuit - Krista Pärmäkoski (Johaug was at this, and won overall, plus obviously 2 of the 3 stages are pursuits which are contingent on other races)
Dec 4, 2016, Lillehammer - 10km classic pursuit - Krista Pärmäkoski (Bjørgen and Kowalczyk there, no Johaug)
Dec 10, 2016, Davos - 15km freestyle - Ingvild Flugstad Østberg (none of the three)
Dec 17, 2016, La Clusaz - 10km freestyle mass start - Heidi Weng (Bjørgen, no Johaug or Kowalczyk)
Jan 3, 2017, Oberstdorf (Tour de Ski stage) - 10km skiathlon - Stina Nilsson (none of the three)
Jan 4, 2017, Oberstdorf (Tour de Ski stage) - 10km freestyle pursuit - Stina Nilsson
Jan 7, 2017, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Stina Nilsson
---at this point Johaug's suspension takes place, and Bjørgen and Kowalczyk are doing reduced calendars so their performances are not as representative---
Nov 26, 2017, Ruka - 10km freestyle pursuit - Ragnhild Haga (Bjørgen only)
Dec 3, 2017, Lillehammer - 15km skiathlon - Charlotte Kalla (Bjørgen only)
Dec 10, 2017, Davos - 10km freestyle - Ingvild Flugstad Østberg (Bjørgen only)
Dec 16, 2017, Toblach - 10km freestyle - Charlotte Kalla (Bjørgen only)
Dec 31, 2017, Lenzerheide (Tour de Ski stage) - 10km classic - Ingvild Flugstad Østberg (none of the three)
Jan 1, 2018, Lenzerheide (Tour de Ski stage) - 10km freestyle pursuit - Ingvild Flugstad Østberg
Jan 4, 2018, Oberstdorf (Tour de Ski stage) - 10km freestyle mass start - Ingvild Flugstad Østberg
Jan 6, 2018, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Heidi Weng
Jan 21, 2018, Planica - 10km classic - Krista Pärmäkoski (Kowalczyk only)
Jan 28, 2018, Seefeld - 10km freestyle mass start - Jess Diggins (Bjørgen only)
Mar 4, 2018, Lahti - 10km classic - Krista Pärmäkoski (Bjørgen only)
Mar 17, 2018, Falun - 10km classic - Krista Pärmäkoski (Bjørgen only)
Mar 18, 2018, Falun - 10km freestyle pursuit - Jess Diggins (Bjørgen only)
---Johaug returns, Bjørgen and Kowalczyk retire---
Dec 30, 2018, Toblach (Tour de Ski stage) - 10km freestyle - Natalia Nepryaeva (no Johaug)
Jan 2, 2019, Oberstdorf (Tour de Ski stage) - 10km classic mass start - Ingvild Flugstad Østberg
Jan 3, 2019, Oberstdorf (Tour de Ski stage) - 10km freestyle pursuit - Ingvild Flugstad Østberg
Jan 5, 2019, Val di Fiemme (Tour de Ski stage) - 10km freestyle mass start - Ingvild Flugstad Østberg
Feb 17, 2019, Cogne - 10km classic - Kerttu Niskanen (no Johaug)
Mar 23, 2019, Quebec - 10km classic mass start - Stina Nilsson
Jan 1, 2020, Toblach (Tour de Ski stage) - 10km classic pursuit - Ingvild Flugstad Østberg
Jan 3, 2020, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Astrid Uhrenholdt Jacobsen
Mar 7, 2020, Holmenkollen - 30km classic mass start - Frida Karlsson
---Norway skips half the season due to coronavirus pandemic---
Dec 13, 2020, Davos - 10km freestyle - Rosie Brennan (no Johaug)
Jan 2, 2021, Val Müstair (Tour de Ski stage) - 10km classic mass start - Linn Svahn (no Johaug)
Jan 3, 2021, Val Müstair (Tour de Ski stage) - 10km freestyle pursuit - Jess Diggins
Jan 5, 2021, Toblach (Tour de Ski stage) - 10km freestyle - Jess Diggins
Jan 6, 2021, Toblach (Tour de Ski stage) - 10km classic pursuit - Yulia Stupak
Jan 8, 2021, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Natalia Nepryaeva
Jan 10, 2021, Val di Fiemme (Tour de Ski stage) - 10km freestyle mass start (Alpe Cermis - lengthened from 9km to 10km) - Ebba Andersson
---Norway returns---
Jan 29, 2021, Falun - 10km freestyle - Jess Diggins
Jan 30, 2021, Falun - 10km classic mass start - Linn Svahn
Mar 13, 2021, Engadin - 10km classic mass start - Yulia Stupak (no Johaug)
Mar 14, 2021, Engadin - 30km freestyle pursuit - Heidi Weng (no Johaug)
Nov 27, 2021, Ruka - 10km classic - Frida Karlsson
Dec 4, 2021, Lillehammer - 10km freestyle - Frida Karlsson
Dec 29, 2021, Lenzerheide (Tour de Ski stage) - 10km classic - Kerttu Niskanen (no Johaug)
Dec 31, 2021, Oberstdorf (Tour de Ski stage) - 10km freestyle mass start - Jess Diggins
Jan 3, 2022, Val di Fiemme (Tour de Ski stage) - 10km classic mass start - Natalia Nepryaeva
Jan 4, 2022, Val di Fiemme (Tour de Ski stage) - 10km freestyle mass start (Alpe Cermis) - Heidi Weng
I've underlined the ones that you could consider legitimately beating the big guns when they were present, although I'm not so sure about counting a number of the stages of stage races where they may just have defended the yellow bib or not needed to contest the stage win, and those count for a considerable number.
You'll actually notice that the number really plummets actually when Johaug returns from her suspension, there was much more opportunity for outsiders, unbelievably, while Bjørgen and Kowalczyk were still active. This is also possibly a legacy of the homogenisation of the calendar and the significant reduction in longer races with very few skiathlons, 15k races and of course only a couple of 30ks a season (where Karlsson seemed to have the measure of Therese a bit recently, almost catching her as she tired in the Meråker pursuit and successfully doing so in the Holmenkollen 30k in 2020), meaning much less opportunity to compete with her - Johaug has shown lately to tire in 30ks, I know today she dominated and all, but Karlsson seems to be Nils van der Poeling her efforts in the format whereas Therese goes out hard, builds a gap, and keeps going and holds on - she knows full well that 10k which is what 90% of distance races for women on the World Cup are is well within her threshold of how far she can go all out, so she just goes all out start to finish and wins and never tires. FIS seems to thereby think that increasing the number of sprints and short races to give others a chance is the way to go, but it's just killing distance, when in fact a greater disparity between the shortest and longest races would be better as it would increase variety rather than the huge homogenisation of the calendar into a limited number of formats adn distances.
However, the fact Johaug has been in fact MORE dominant (even taking into account sharing the snow with Bjørgen before it) in the four years since returning from her suspension at 30 is eye-catching and much like Bjørgen, Sundby, Tora Berger and Røiseland, she seems to have her best period of dominance in her early 30s.