I was part of a conversation with a person looking to GM Monster of the Week along these lines on RPGGeek, recently. After that conversation, I think part of the problem some people have with PbtA games is “freeform until a move triggers” sounds very similar to “the GM tells you what happens between move triggers”, which feels in the neighborhood of “the GM railroads you when a move isn’t triggering”.

This is true even if you are a GM. This person, for example, found it very strange that he was essentially not allowed to roll dice when it seemed like a good time to roll dice, that he was required to use “GM fiat” (his words, I think) to determine outcomes that in any other game he would let the dice decide.

If it is of any interest, here is the thread: https://rpggeek.com/thread/1692919/what-do-you-do-when-running-monster-week-different