(Free) [STEAM] Street Fighter II

Going off the title and store page, it's "The World Warrior", the initial base game version of SF2, which is.. basically worthless.
Purists would instead go for "SF2: The Championship Edition", which allowed for players to select the same character [ie, Blanka vs Blanka] and balanced out key game inbalances, while the majority would go for "Super SF2: Turbo", which increased playing speed to be more in line with fighting game player expectations and introduced super combos.

And that's just the original releases! There's also been the well-received rereleased versions of the game (Turbo HD Remix, Ultra SF2: The Final Challengers, and Hyper SF2) that were released in the years between SF2's original release and now.

Nevermind that of the classic formula games, SF Alpha 3 is generally considered the best offering overall (eg, on balance and general gameplay smoothness), and also has the largest roster, so anyone looking for a legacy SF game for reasons other than nostalgia would presumably go for that game instead, to begin with. Of course, while SF Alpha 3 is more derivative of the SF2 formula, and thereby a bit more topical, SF3: Third Strike also has its fair share of supporters in being the "best classic SF game", making for yet another more viable alternative option.

[TL;DR version:] So yeah- it's interesting as a legacy piece (and for some of us, for the nostalgia), but it's really not much of a freebie. Rather, by this point, it's more bizarre that it's not permanently free, especially given that it's part of a launcher, where you'd absolutely expect some basic offerings to be free to get you to look into the platform in the first place.

So, while you were presumably already being sarcastic in your comment, I'd dare say you were actually still not being sarcastic enough.. 🙄