I agree with you. We saw this year many mountain stages with big groups coming together, including with Caruso, Valverde and others subpar performers. The time differences between the cyclists is very low (specially looking to the GC yesterday) comparing to previous years. This all points out to a rather weaker-than-usual field, which can be explained in many ways. WVA, De la Cruz, Cavagna or Porte are also very surprising results.
There is clearly a transition in the peloton, with many sub-23 cyclists riding at an incredible high level. This is very uncommon in cycling and points out to a rather weaker field for those in the 20's / 30's.
Obviously the huge difference, UAD / Aderlass brings a shadow to this result, but i would not compare Pogacar to Ricco / Piepoli / Schumacher...