"Quitting your job to make games" is just like quitting your job to write your novel

I think it's actually worse since you can't directly make money from the game while making it. You can stream for example, but it requires a completely different skillset.

Compare that to, for example, writers releasing chapters on royal road, getting some funding through patreon while writing (in return for advanced chapters), and quitting their jobs when the book sales pick up. Like yeah it's still really hard to make good money, but the possibility of slowly progressing into full time writing is why people can try to do it.