While it's not easy (and you should never trust anyone who says that it is), I do think that it's more feasible than most developers think it is. I'm not special, absolutely far from it, and I achieved it (in Australian dollars anyway, and focused on a B2B niche rather than B2C)

If you're going to engage in fraud anyway, you can make more than you'd pull in from working two jobs

Hell, with all the crypto madness going on right now, you could probably get ludicrously wealthy just doing freelance black hat security testing.

You aspiring fraudsters should actually read all the paperwork they put in front of you next time you start a job, and tell me if there's no exclusivity at all in it. Just because Jack Dorsey got away with running two companies doesn't mean it's right or just for you to weasel along and lie to two managers forever.

Get your life together and do something meaningful instead of stressing yourself out for the sake of whatever pair of pittances you can earn from this dumb scam.