mechanical-puzzles has 7 questions. Its wiki says:
Puzzles that are physically made and have some sort of mechanism for turning or moving them, such as Rubik's Cubes or trick boxes.
twisty-puzzles has 4 questions. Its wiki says:
The twisty-puzzles tag is for all questions related to solving or discussing Rubik's Cube related puzzles.
Do we really need them both, or can one be made a synonym of the other?
If the community opts to synonymize, I'd suggest synonymizing twisty-puzzles into mechanical-puzzles.
One is a subset of the other, so a synonym could still be a valid option. Additionally, there are many people out there who see "twisty puzzles" as the name for all Rubik's cube variants, even if it isn't the descriptor we would like to use.
As a result, while this isn't technically a "synonym," there are a couple good reasons I can think of to apply a synonymization here. I'd be in favor of it.
"Mechanical puzzles" refers to most physical puzzles, twisty or not - Sliding tiles (15-puzzle), ball mazes, take apart, put together, etc. The wiki for it just needs to be broadened appropriately.
