https://steamspy.com/year/8,243 games were released on Steam in 2019 and 3,434 so far in 2020.
Unless you approach indie development like a business and you have a concrete plan for gaining a following, your chances of making a living are near zero. That's not to say you shouldn't do it, but don't expect to make a living doing so.
As an example, David Brevik (of Diablo and Diablo2 fame) spent several years working on It Lurks Below -- a procedurally generated roguelite/dungeon-crawler. According to SteamSpy [1], he's sold 20k-50k copies at around $15-20 per copy, and as of today the game only has about 20 peak daily players.
So probably $500k-$1M in gross sales (and then Steam takes 30%) for someone of his caliber and reputation, after 3+ years in development and a year or so since initial sales. It's just an unbelievably difficult chance of making it financially viable.
[1] https://steamspy.com/app/697550