Mihai Simion (and Vayer) had him at 8 w/kg.
Of course the number could be higher for a one minute effort.
If Vayer can possibly make it look any more suspicious, he will not hesitate to do so

He's pulling what's left of his hair out, because a rider from Quickstep is the first French Worldchampion since a rider from Festina.
That said, i don't know which is correct, just a bit predictable that Vayer & co would come up with a higher number.
MVP and AERTS have this too to an extent. I think it's from the requirements of their level of cyclocross. Massive bursts of sustained power then recovery.
I know what you mean with Mathieu, though it is still completely different compared to Alaphilippe. But Aerts? He's a good climber for his size/weight but i can't remember him dropping anyone like that on a regular basis. If anything, i'd probably say Iserbyt or Pidcock. Mini-Nys already ridicules Aerts on these types of things.