EA doesn't support this. It's absolutely not okay to do immoral things to make money and even things like Earning to Give via legit quant roles is and was pretty hotly debated.
It's all very well to pay lip service to 'common sense morality' but it doesn't seem to fit into the actual theology of EA, and this is what fanatics are most likely to follow.
Even if you find a "pure" utilitarian (which is rare), it's considered "naive utilitarianism" to ignore the long-term and broad effects of creating harm, and it's also considered intellectually arrogant to think you know enough about the impacts of your decisions and moral philosophy that you can justify causing definite short-term harm for potential long-term gain against the moral frameworks of just about everyone else.
On the whole, I can't personally think of any one person involved in EA, or widely-read EA literature, that promote or support that type of thinking.
Because most people who are willing to donate x% of their salary to charity tends to be decent people? Apart from that, there's tons of fundermental EA posts and writings that talk about how EA cannot be an 'ends justify the means' philosophy to donating. Sadly this SBF shit has really corrupted the core message which is to be skeptical of charities and view them like investments, picking the best one for QALY per $, and valuing all lives equally. I don't even like the futurist side of EA because I personally can't put the value of a hypothetical person above someone who's sick today and focus on global health & animal welfare. Honestly the core point of EA is imo very hard to discredit aside from longtermism.
I’m curious if you would accept the claim that a regular churchgoer is unlikely to act immorally, because I can’t see any difference in principle, down to the “donating a portion of your salary” part.
This is at odds with its core adoption of utilitarianism, which is the movement's fundamental justification. Utilitarianism is sort of textbook "sounds nice on paper, works crappy in practice" outcome.
So you can conclude that you should just do whatever makes you feel good and all ethics are nonsense as you seem to prefer, but I'm not sure that you've really refuted the basic premise that you should try to maximize the amount of good you can accomplish.
I say this as someone who took the Earning to Give path from 80,000 hours and happily donate to healthcare charities suggested by Givewell via Giving What We Can. My wife took the other path and is a postdoc at Stanford working on medical research with an EA focus (both in her field and on replication crisis in medicine). I'm pretty in this space so to speak, albeit only in a small way.