So what about Vingegaard?I think you have to ask was there a guy who could crush Merckx in top form in the mountains? Yes there was, Luis Ocana. And is there a guy who can crush Pogacar in top form in the mountains. No there isn't (at least for now, and unlikely if he remains so till 2030).
True Merckx was put in trouble by Ocana , but he already had his long term injury, and was he in ‘top form’ the day Ocana put that time in to him? Who knows.
True also that Pog may have been a little young to say he’s truly prime when Vingegaard beat him , but he’d already won the last two tours and beat prime Roglic.
History says that Pog cracked and lost to Vingegaard twice, Merckx was put in trouble, fought back and fortune favoured him and he won the only tour where he struggled somewhat.