Gabe Newell is the least shitty billionaire I can think of, I'm not sure what he does for philanthropy though but at least it doesn't seem like he tries to influence the country for his benefit.
I love Valve, but I really don't understand why gamers give Steam so much praise. It is a closed platform filled with DRM on which you don't truely own a copy of the game (unlike gog), and on top of that they take a 30% cut of every sales and transactions which is enormous for small studios to pay. Support is poor and the algo/front page distribution of traffic and promotions is a black box.
Don't get me wrong, Gabe seems like a sensible human, and Steam is successful because it offered such a great service to players. But it's been almost 20years now since Steam, and I have not seen Valve slow down the greed. They don't need the money as this point. They don't need 30% of every game sale on PC. This is just as greedy as the other company people hate.