According to a report from IGN, the short answer is no. This was confirmed by Valve at the Steamworks Steam Deck event where they said they aren’t interested in developers creating exclusives for the Steam Deck. The company says that since the Steam Deck is meant to emulate a PC, and as such it should play games like a PC.
Of course, there are titles that are developed for PC specifically and not consoles, but we wouldn’t necessarily consider those “exclusive” since as long as your PC meets the system requirements, you can play it. This is versus consoles where you would actually need to purchase the console to play console games. This is obviously good news for gamers who might be worried that developers might create games that would be limited to the Steam Deck.
For those unfamiliar, the Steam Deck is essentially a handheld console that would play games from the gamer’s Steam library. So if you already own games on Steam, it should work on the Steam Deck and you wouldn’t be required to purchase it again.