When you go into a store and buy something, you tend to leave with a physical product. Not so with Steam.
You mention a "library" of games...when you take something out of the library, it's not yours.
How do you normally access your games? Through the Steam platform, or by running executables directly from your machine (without needing an internet connection)? Because if you usually use the Steam platform, that was the first hint that you don't "own" the games. And if you need an internet connection, that was the second hint.
Another big hint is, as you said, the game is tied to your account. Not your person. Your account is explicitly non-transferable (e.g., in death). As well, they can remove your access to your account for not being in line with the T&C.
You buy a drill from a store, then you use the drill to break someone's lock. But you still own the drill -- neither Home Depot nor Ryobi has a legal right to take that drill away from you, even if you get caught.
Again, I'm not defending Steam here. This is why I recommend people look into DRM-free services like GOG if you actually care about "owning" your games.
Otherwise, good luck with your class-action lawsuit against Steam. It's not like I have an empty Steam library, so if a class-action actually won, I'd benefit from that too. I just don't think it'll ever happen, thanks to the T&C which most people seem to generally know and accept.