Doesn't matter for how they're measuring. None of those games are marked as either Verified or Playable by Valve, so they're not included in these statistics, despite working fine on the Deck.
That is true, a lot of games can be played easily with the WASD + Mouse keybinds. Not unusable by any means, but it can be frustrating for people who get thrown off by the on screen prompts corresponding differently than what their controls actually are.