Depends on the sector. If you’re a software engineer or white collar worker, leaving your job for a prolonged period of time is a matter of planning and frugality.

Speaking only for myself, I intentionally lived in a small apartment in order to make sure I had at least a year of income saved. I did this pretty early in my career in the bay area. I believe it’s still quite possible to do this if you are willing to forgo purchases that signal wealth (i.e, live in the smallest manageable apartment, keep driving your beater for a long time, cook instead of eating out).