I think that the priority first should be to organize something in a civil manner (can't emphasize this part enough) to campaign positive change, with the idea of spreading awareness.
I've grown tired of Valve's selective quality control. This has become a bit of a frustrated vent of sorts, but I've gotten burned out from too many bad game launches that often never get resolved. Steam forum users have no backbone to speak up about problems (and they actively defend them), these same people positive-bomb games with useless joke reviews despite only spending seven minutes in the game, and people think it's all acceptable now that a refund system exists and "don't preorder" r/PatientGamers circlejerking (that is tonedeaf to problems) is constantly being peddled. The only way Atelier Ryza, Nier Automata, or Batman: Arkham Knight ever got fixed was because of consistent feedback and utilizing customer outlets. It's also impossible to find interesting indie games or Visual Novels on the Steam store (Because it's flooded with shovelware), and yet Valve somehow thinks that what they're doing now with their inconsistencies regarding what stays is going to be remotely sustainable. I've known that their quality control has gotten worse over the years, but this is a new low. Steam forum users will whine about Disgaea 6's pricing (despite being a good port and coming with the DLC), just to then buy Omega Labyrinth or something similar for $60 (with an extremely barebones/flawed port for the asking price) and a ton of DLC shoehorned in, it's hilariously twisted priorities at best. Or the fact that Steam users campaigning for a restoration patch for Mary Skelter 2 stopped at that and bent over despite the many other problems with that release. The plenty of straight PSVR ports that are locked at 60FPS and have insane judder and reprojection problems on 75Hz/90Hz/144Hz VR headsets that pose as a health/epilepsy risk despite being certified for the Oculus Rift and HTC Vive (both which are 90Hz)? Or dare I speak about Elden Ring and it's plenty of port problems that haven't been resolved outside mods that require cutting a chunk of the game out (multiplayer) to use? I've seen my fair share of Steam releases where you are frankly better off buying on Switch, dumping a ROM of it from your system, and then emulating it with whatever resolution or controller you want.
Valve has also made it progressively more difficult to roll back game updates (and also hampering sites like SteamDB's ability to operate, despite being a useful tool to many) because certain publishers got mad. The community had to petition Capcom to add the old RE3/RE2R/RE7 builds to a beta branch on Steam because of how behind the times Valve is in that regards. Valve has actively prevented tools like Special K from getting a Steam release while also allowing borderline malware or snakeoil tools in their software section. Valve pulled a Nintendo regarding Team Fortress 2 Classic having to reverse engineer how the game worked. They don't care about modders actively being forced into making games better (Because there's this growing expectation in the community of modders having to fix everything for free when the skills to do that are high AND are quite often hard to find (or gatekept by certain online sources)), only if it improves their bottom line, I don't even recall the last time Valve has actively hired modders.
You can also make an alternate region account on consoles to buy region locked games, and yet Valve still makes account switching on Steam (My Steam Deck is the most convenient thing to play Idolm@ster and a couple of other games on because desktop mode constantly requires entering your password and Steam Guard code) or creating an alternate region account increasingly difficult to do. This is just going to further incentivize piracy (I don't recommend it for many reasons), because Steam has a massive service problem from years of neglect, complacency, and being pushovers. People love to talk smack about Epic Games being publisher pushovers, but people really don't criticize some of Valve's decisions enough because of a handful of positive things.
There's really a ton of things that could be glanced from a campaign, we'd just need a public figure to bring awareness to these many problems with Valve and Steam.