I can see where this might be the sort of thing that people have joked about playfully, as if to point out the bizarre coincidence that so many doors in a single building would have so many broken locks. But I doubt it goes much deeper than that.. I don't think people are "genuinely annoyed," as you put it, by the number of broken locks in Silent Hill games lol.

I mean, anyone with even the slightest shred of common sense would be able to figure out that the broken locks are just the game's way of putting a limitation on the areas the player can access.

When it comes to the early Silent Hill games especially, people are well aware that these games come from an era in which it was not at all uncommon for games to be more linear, and less likely to allow the player to go anywhere they want.