I know it's a nit-pick, but I hate that this always gets brought up when it's not actually true. Public corporations face pressure from investors to maximize returns, sure, but there is no law stating that they have to maximize profits at all costs. Public companies can (and often do) act against the interest of immediate profits for some other gain. The only real leverage that investors have is the board's ability to fire executives, but that assumes that they have the necessary votes to do so. As a counter-example, Mark Zuckerberg still controls the majority of voting power at Meta, so he can effectively do whatever he wants with the company without major consequence (assuming you don't consider stock price fluctuations "major").
But I say this not to take away from your broader point, which I agree with: the short-term profit-maximizing culture is indeed the default when it comes to publicly traded corporations. It just isn't something inherent in being publicly traded, and in the inverse, private companies often have the same kind of culture, so that's not a silver bullet either.
Valve is one of my top favorite companies right now. Love the work they're doing, and their products are amazing.
Can hardly wait for the Steam Frame.