I truly believe that Valve has two fundamental things working in their favor:
Firstly: Despite inventing or at least popularizing a lot of new microtransaction concepts, they've just never been the greediest company in the business when it comes to microtransactions. Mobile gacha games have cleaned up their business quite a lot lately, with most of them being significantly less predatory than they used to be, but even back when TF2 introduced lootboxes and hats, the important thing was that the game was not pay to win; you could get all of the items in relatively short order just by playing, and the only benefit to paying was cosmetics.
Contrast this to the earlier reign of Korean MMOs: pretty much all of them had egregious microtransactions. MapleStory, PangYa, Gunbound, etc, and even some current platforms like Roblox. Valve also came into this whole thing before lootboxes became the root of all evil, and while TF2's lootbox mechanism looks bad in retrospect, there was simply no stigma against a system like that, and it never felt like a big deal during the game's heyday. Just my opinion, but I strongly believe it to be true.
Secondly: The most egregious things going on are not things Valve is directly involved in, they are merely complicit, in that they don't do much to curtail it. It's not even necessarily cynical to say that Valve is turning a blind eye, they benefit so significantly from the egregious behavior that it is hard to believe they are not influenced by this fact. But: It is consistent with Valve's behavior in other ways: Valve has taken a very hands-off stance in many places, and if it weren't for external factors it seems likely they would be even more hands-off than they are now. I think they genuinely take the position that it's not their job to enforce moral standards, and if you really do take this position seriously it is going to wind up looking extremely bad when you benefit from it. It's not so dissimilar from the position that Cloudflare tries to take with its services: it's hard to pick apart what may be people with power trying to uphold ideals even when it is optically poor versus greedy companies intentionally turning a blind eye because it might enrich them. (And yes, I do understand that these sites violate Valve's own ToS, but so does a lot of things on Steam Workshop and elsewhere. In many cases, they really do seem consistently lax as long as there isn't significant external pressure.)
Despite these two things, there is a nagging feeling that every company gives me that I should never take anything but a cynical view on them, because almost all companies are basically lawnmowers now. But I really do not feel like I only give Valve the benefit of the doubt just because they support Linux; I actually feel like Valve has done a substantial amount to prove that they are not just another lawnmower. After all, while they definitely are substantially enriched by tolerating misuse of their APIs, they've probably also gotten themselves into tons of trouble by continuing to have a very hands-off attitude. In fact, it seems like owing to the relatively high standards people have for Valve, they get criticized and punished more for conduct than other companies. I mean seriously, Valve has gotten absolutely reamed for their attempt at adding an arbitration clause into their ToS, with consequences that lingered long after they removed and cancelled the arbitration clause. And I do hate that they even tried it -- but what's crazy to me is that it was already basically standard in big tech licensing agreements. Virtually everyone has an insane "you can't sue us" rule in their ToS. It numbs my mind to try to understand why Valve was one of the first and only companies to face punishment for this. It wouldn't numb my mind at all if it was happening to all of them, but plenty of these arbitration clauses persist today!
So when I consider all of this, I think Valve is an alright company. They're not saints, but even if the bar wasn't so terribly low, they'd probably still be above average overall. That can be true simultaneously with them still having bad practices that we don't all like.