It will, but he meant games that have control schemes designed for controller inputs, because that’s the easiest way to get started with the deck in handheld.

Steam input is extremely powerful and can be set up to make pretty much anything playable with the inputs the deck provides, but because the game won’t tell you the controls (and you might need to manually set it up), it’s more of an adjustment.

While I ignore “deck verified”, if you want to stay safe until you’re more comfortable, valve’s “great on deck” part of the store/library is pretty helpful.