The good thing these days is that there are so many more ways that professional players can make money in chess, which is nice.
I’ll try to give a reasonable example using four different GM friends of mine...
Hikaru Nakamura: All Hikaru does is play. Yes, he has sponsors and makes money like that too, but his main profession is strictly to play.
Josh Friedel: Josh plays quite a bit. But he also teaches, writes some articles, makes some videos, etc. Josh dabbles in a bit of everything.
Mesgen Amanov: Mesgen doesn’t play at all anymore. All he does is teach and sell his video lesson courses. Mesgen’s primary income comes from coaching.
Eric Hansen: Eric is one of the new breed of GM’s. He plays a little, and writes a tiny bit, but doesn’t really coach at all. However, he’s on the leading edge of making chess a legit e-sport. He streams a lot. Whether it’s blitz/bullet on Twitch, or covering events like the World Cup or Norway Chess on streams.
So the answer as to how people can become chess professionals is far more complex than its ever been. But with a lot more opportunity.
Op didn't seem to get that a professional should be worried about making money out of their profession