except for pogacar, there are no other riders in the peloton with ability to attack and sustain that attack for longer period of time (vs top competition) - pogacar did it in tirreno, did it in tour de france and even he was then unable to do it again in 3rd week
everyone else rides to slowly drop competition first, either by himself or with help of teammates, usually the tempo is setup so high an attack from group of favourites doesnt last for long
seems to me that yates is capable of doing it but wastes his energy that way, carapaz possibly too but again it worked only once in tour de suisse (olympics were more of a result of breakaway riding than attacking on a climb), bernal did it but against weaker competition and its not exactly a strong point for roglic either - his thing is killing oponents by chipping away 15 seconds here and there, by the third week he is up 60 seconds
it just looks like unless its Pogacar in top form, nobody dares to attack early and keep going, because to do that you would have to push 6,3 -6,5 w/kg so no other favourite can follow including their domestiques