Concerns expressed by FIRE movement followers

I read a book by someone who retired early (FIRE) after making 5 billion won through stocks.
However, they mentioned that they aren't actually that happy.
They were a university professor, and the moment they resigned, their professional relationships were severed.
They wrote that they only see friends occasionally and feel extremely lonely.
They said that achieving financial freedom and living a happy life are two different things.
They explained that while money makes time free, it cannot make that time meaningful.
They spoke about how life becomes difficult without a sense of belonging, human relationships, or a social role.
Do you agree with this?