Yep, you know how things go, often in the way you would never expect but afterwards it seems it could not happen any other way... this for the most recent example is less bold of a claim than Pogačar not winning the tour for the next 3 years after the 2021 Tour and I think you don't believe he will win this year. Or the one before that, who would have thought on top of Col de la Loze in 2020, that Roglič will not win that Tour... or the one before, how many Tours in coming years did people think Bernal would win after the Tour 2019, etc...
The descent from the peak will always hit you sooner than you would have expected it, some of it is because of time up there flying... while sometimes others surprise us sooner yet.
for a funny stat: pretty sure nobody has ever won a stage race where both Roglič and Pogačar were competing against them and that's quite a "spell" to break (or competition to beat).
(edit: eh, there is that Dauphine 2020... can't have that again... but yet another case of how easy is it not to win a race, even when you are clearly the strongest... let alone when you are not)