Correction, for Steam users, not for everyone.
Steam Input and Workshop are completely proprietary services that do not work outside of Steam. Steam Input configs are difficult (not impossible, but unnecessarily complicated) to access/share across services, meaning that even if you do use Steam, if you bought a game outside of Steam and are importing it, you're probably going to be rebuilding the Steam Input config from scratch. Steam Workshop is also inaccessible to games purchased outside of Steam even if you import those games into Steam. And not only has Valve not built a way to link imported games to a Workshop and not provided mechanisms for games to make use of Workshop outside of Steam as an independent service, the company has actually clamped down on efforts to circumvent that DRM and shut down community projects.
Both Steam Workshop and Steam Input are very clearly designed to be vendor lock-in. To gamers who only use Steam and nothing else, it feels like Valve is making it better for everyone, but it's a lot more like the Apple ecosystem -- Valve is leaving behind anyone who buys games outside of Steam and almost explicitly punishing users who get games from other storefronts. The company offers a lot of services that can't be debundled from Steam -- you can't as a developer pay Valve to make use of Workshop outside of Steam. And so a lot of these "universal" benefits are really only benefits for people who buy games exclusively on Steam.
That's not to say Valve doesn't do great work elsewhere. Proton is genuinely good for the ecosystem, even though Valve still ties it heavily into Steam and combines it with Steam-specific features like shader caches that are inaccessible outside of Steam. I think the Steam Deck is a wonderful device hampered only somewhat by the fact that it's so reliant on Steam Input which is entirely proprietary. But it's still miles above other consoles and I'm genuinely grateful that Valve built it and even more grateful that they based it on Linux. It's repairable, it's far more open than other consoles. Valve might "punish" users for installing 3rd-party software on it but at least installing that software is allowed.
Valve is neither perfect nor evil. People get enamored with Valve because our standards for companies have fallen so unbelievably far, to the point where just allowing people to install 3rd-party software and responsibly contributing back to an ecosystem that Valve is heavily reliant on feels like being granted an unexpected gift. We're used to companies abusing consumers even when there's no reason to do so. And so Valve saying "yeah, it makes more sense to us contribute upstream and it makes sense not to treat our customers like crap" is a refreshing difference.
But Valve is still a company and is still willing to prioritize its own hold on the PC marketplace over consumer and developer rights; it has plenty of vendor lock-in and plenty of proprietary services and systems that are designed to make it so that you as an end-user can buy the exact same game on two platforms and run both versions on the same device, and one of them will literally perform worse, will be harder to configure, and won't have mod support.