If it's tricky for people in software engineering (those still holding a job continue to have big salaries compared to most other industries) to have hobbies they are willing to pay for themselves, it's probably them finding excuses instead or living beyond their means.

Nope, there are still people doing this stuff to share what they are excited about, and they will continue to be people like that.

Economy has nothing to do with this — as mentioned, a lot of this comes out of university students and low rung staff, and they were never best paid.