do you get the game when you download it from here or do you just get the steam key to get it
The itch.io version is an "unsupported platform" and you can't create or use an account here. That locks out a lot of game content (including the ability to use a name of your own choice, and free chat) so functionally you only get the Steam version.
Thanks to Valve turning the Steam client into a health hazard almost 2 years ago (and blocking access to any safe workarounds since), I was forced to refund the game on itch.io because I don't have the full game here. I was able to get the game on Epic (as bad as they are, still better than Valve at this point) so I can still play.
it's because of at least half a dozen different problems, all of which showed up in the "new library" update in 2019, and most of which are long-standing known problems for numerous medical conditions which everyone (except apparently some idiot at Valve) knows better than to include in a game launcher app.