Since you haven’t given any kind of number for the number of sprinters in the 90s vs 2010s, though it’s less but I’m unable to find how much less, here’s some numbers for you.
For the seven riders you picked this is the amount of times they beat Cipollini;
Steels 3
Blijlevens 2
Minali 2
Svorada 2
Abdoujaparov 1
Zabel 1
Baldato 0
11 times
73 total GT stage wins for the seven riders.
11 GT points classifications
For Cavendish’s years you selected this is the riders that beat him;
Petacchi 4
Bennati 3
Farrar 3
Greipel 2
Hutarovich 1
13 times
88 total GT stage wins for the 5 riders.
6 GT points classifications
And for the Cavendish years I selected 2007-2014;
Greipel 4
Petacchi 4
Bennati 3
Farrar 3
Kittel 3
Ferrari 1
Guardini 1
Hushovd 1
Hutarovich 1
21 times
124 total GT stage wins for these 9 riders
9 GT points classifications
During the more fair timeframes for both riders:
Cipo won 35 GT stages, 2 GT points classifications, 15 GTs started, and 105 total wins.
Cav won 43 GT stages, 3 GT points classifications (and could have had 6 with more luck or a better head on his side), 15 GTs started, and 120 wins.
So was Cipo’s competition actually better or did they just benefit from him not showing up or abandoning the race on top of making a career out of sprinting being new at the time? Or were Cipollini, Petacchi, and Cavendish that much better than everyone else? Since the 2000s we have seen sprinters older then 25 still be able to win sprint stages and sometimes multiple times during a GT edition. Could Cipo have won more, absolutely but he decided to abandon a lot of the races instead of riding in the mountains. Why are we going to further knock a rider who actually attempted to finish every GT he started?
I didn't respond before as it just seemed to be going in circles, but as you insist, there was just as many sprinters in the 90s as there was in any other era. On top of the riders I listed there was also Moncassin, Van Poppel, Neliseen, Ludwig, Bontempi, Kirsipuu, McEwen, O'Grady, Wust, Leoni, Baffi, Quaranta, Magnusson, Guidi etc, etc.
Right through the 80/early 90s, there were far less sprint stages as teams were not really dedicated to sprinters, though they sometimes chased down breakaways in an effort to set up sprints, but leadout trains were pretty limited and you had riders like DeWilde, Nijdam, Marie who could still skip off the front in the final km and win. Something that is almost non-existent nowadays. For context, there were as many sprint stages in this years Tour as there was in the 89/90/91 Tours combined, throw in 92 and it wouldn't change much.
Cipo moved to the MG-GB team in 92 and had a bit of a leadout, but at the Tour that year, there was not a single sprint finish until the second week so clearly his team were not effective in setting up sprints. The second sprint finish was in Paris that year. After that things started to evolve, but Cipo pretty much missed all of 94 because his own team-mate Baffi took him out in a sprint at La Vuelta, thereafter we see the development of Cipos Red Train at Saeco which to me at least, was the beginning of proper sprint trains and saw a big increase in the numbers of bunch sprints at Le Tour thereafter. At that stage Cipo was already 27.
I am not sure what your stats are trying to demonstrate, but the figures for rides who competed against Cav are heavily skewered by one rider Petacchi who has 50 GT wins and was 36/37 when he went up against Cav at the Tour in 2010/11. Does anyone really believe he was at his peak at that point in his career? Bennati 11 GT wins, rode the Tour in 09 having missed 2 months to injury in the run-up, best results 9th in 2 bunch sprints. Then Greipel with 22 GT stage wins, rode once in 2011. Riders between them with 83 GT stage wins out of 88.
If you had a Bennati with 07/08 form, along with peak Petacchi, Greipel and sprinter Boonen racing in Le Tour from 08-11, then you could compare to Cipo against Zabel, Steels, Blijlevens etc. In that case I would be confident Cav would not have taken 20 stages in 4 years which is the whole point.
I am not even arguing Cipo is better than Cav. I am pointing out that using numbers to show who the best sprinter is kinda pointless as each era was different in its own way. If Cav had raced in the 80s, he would not have won a World Title or Milan-San Remo or 34 Tour stages or if he had been born in Italy and raced in the 90s, the Giro might have been the focus and the same goes for Cipo or most modern sprinters. So how can anyone claim they were the greatest based on numbers?
As an aside, in an issue of Cycle Sport from 2001, there was an article on the greatest sprinter of all time. Cipo had 12 Tour stages, over 30 Giro stages, two Ghent-Wevelgem and countless other wins at that point. He was ranked 9th on the list according to Barry Hoban(Sprinter from the 70s) and Grame Fife (cycling author). I am not sure his annus mirabilis would have moved him up much as the big criticism was he relied on his team to win, which can be applied equally to Cav. Joint No 1 was Maertens and Darrigade.