Your system information

• Steam client version:
  Latest stable as of today
• Distribution (e.g. Ubuntu):
  Ubuntu
• Opted into Steam client beta?: [Yes/No]
  No
• Have you checked for system updates?: [Yes/No]
  Yes

Please describe your issue in as much detail as possible:

It should show only SteamOS compatible games everywhere by default, Windows and mac games should be the checkbox, not the other way around.
It's as dumb as showing Xbox games on a PS4, it just shouldn't happen.