It's like most things, real estate.
Most hackerspaces I've been a part of couldn't or barely could afford their rent. Memberships were already too expensive, and they were constantly just getting squeezed between membership revenue and hard costs. Ultimately it doesn't add up.
I think a lot of what used to happen at makerspaces has transitioned to libraries. Lots of libraries have 3d printers, et. Now, are free, and don't have the problem with affording space.