But you're not forcing a result on the PC as far as I can tell.
So, a "condition" would generally be a hard move. And so would be imposed when the rules permit and the GM decides that it follows from the fiction.
The rules of Apocalypse World permit a hard move (i) when a player's adjusted roll for a move is 6 or less, or (ii) when a player hands a golden opportunity on a plate.
This is why I am saying that the key difference is not the mechanics, but the rules that constrain a GM making a hard move.
To give a concrete example: in Moldvay Basic, it's fair game (as far as rules and procedures are concerned) to have deadly traps strike from nowhere. The opening of the chest in the example of play, where Black Dougal dies from a poison needle (because the player fails a save) is an example.
In Dungeon World, on the other hand,
you die from the poison (a hard move by the GM) is not permissible in the absence of a soft move that put the life of the PC at stake in some fashion.
I think they tell quite a bit about what's different from playing OD&D and Monster of the Week (I can't speak of Basic).
OD&D is much the same as Moldvay Basic in this context.
I've run Monster of the Week (in fact, I need to get started on the next adventure) and I haven't found it to be rigid at all. Yes, PbtA games can seem (edit to write in actual English here) that way from the outside ("What if I want to do something not covered by the moves?") but the moves aren't the end-all and be-all of these games. Characters can do anything they want; the Moves are just there if the PCs do something that triggers them. Otherwise, the play, meaning conversation, just continues.
Yeah, but since that's entirely non-mechanical, its also largely irrelevant to system resolution. A lot of it would be handled in general the same way in virtually any game.
But it's not the same in virtually any RPG.
Consider, again, classic D&D (in any of its varieties - Moldvay Basic, Gygax's AD&D, OD&D, etc):
as part of the conversation, it is permitted for the GM to make hard moves (including "nothing happens") just as their prep, and their extrapolation from their prep, dictatees. But in Dungeon World the making of hard moves is governed by completely different principles. Likewise Apocalypse World. I don't know how different Monster of the Week is from these other PbtA RPGs, but I'd be surprised if it's closer to classic D&D than it is to them.