Don't quit your job to invest in bitcoin, it is a very unwise option to take, investing in bitcoin is not a business, neither is it time consuming, so you can keep your other sources of income or your jobs in real life and still comfortably invest in bitcoin.
I think that is quite from his job because the salary was too small, and this happened before he was introduced to Bitcoin. So, he quit not because of BItcoin. AFter quitting, he was introduced to Bitcoin and learned about it.
Fortunately, this really worked on him. BUt I do agree that basically, it is too risky to quit a job and full-time to Bitcoin or crypto. But his case is different.
At that time, I also had no job because of the pandemic and I only could focus on the crypto world. That was very hard to face because the result was also very small and sometimes couldn't fulfill my daily needs. But I couldn't do anything because that condition was different and nothing I could do besides struggling in the crypto world.