Valve has faced criticisms from former employees in the past for its toxic work culture. And Gabe Newell, being the CEO, has a lot of power over that.

Just because the places you frequent on the internet don't shove criticism of Valve down your throat the same way it would do so for, say, Epic Games, doesn't mean there's nothing wrong with Valve as a company. All the pro-Valve/Steam information you get and the general sentiment towards Gabe Newell from people on Lemmy and Reddit are pure, undiluted corporate propaganda. That it comes from Steam users rather than being something Steam directs and pays for doesn't change what it is.

you’re seeing different posts by different people and conflating the two

This ignores the reality that Lemmy is, at least in the part of it consisting of lemmy.ml, lemmy.world, and others, overwhelmingly leftist. This comment also attempts to dismiss the underlying criticism that Lemmy as a whole has a culture that, much like reddit, seeks to pick and choose its targets under capitalism and actively engages in corporate apologia, like in this post, while collectively professing a broad ethos that is outright hypocritical when viewed in the light of that other behavior. And if you think Lemmy is amenable to a diverse array of economic opinions, then maybe you should try posting a "Capitalism Appreciation Thread" on a major lemmy instance and see how that goes over.