The Steam Deck's new user interface is going to replace the increasingly outdated Big Picture Mode at some point, at least according to Valve employees. Steam’s Big Picture Mode was a UI that made it easier for users to play their Steam games on a big screen TV, but it has since fallen out of favor, and has not been updated since 2015.
Steam’s Big Picture mode was especially useful during the era of Steam Machines, which were third-party systems that played Steam's vast collection of PC Games from the comfort of one's living room. These pseudo-consoles never really caught on in the wake of the PlayStation 4 and Nintendo Switch, and Valve quietly removed support for Steam Machines to little fanfare back in 2018. Big Picture Mode has since been an artifact of that ambitious-but-ultimately-ill-fated endeavor, but Valve has recently revealed that it will soon be a thing of the past.
As reported by PC Gamer, a Valve moderator by the handle of austinp_valve was asked if Steam’s Big Picture mode would be replaced by the Steam Deck’s sleeker user interface when the tablet-like system launches this holiday season. “Yes, we are replacing Big Picture with the new UI from Deck," the moderator replied in a post on the Steam Community Forum. "We don't have an ETA to share yet though.”
Valve surprised many when it unveiled the new Steam Deck console out of the blue last week, though there were rumors of a portable Steam device beforehand. While the tablet-style machine has naturally drawn comparisons to the aforementioned Nintendo Switch and storage space for notoriously massive PC games will inevitably be a concern, enough players have been fascinated by the idea of taking their Steam Libraries with them on the go that pre-order reservations are already being scalped on eBay like the PlayStation 5 and Xbox Series X before it. Not everyone has jumped aboard to embrace the Steam Deck though, as Ubisoft recently suggested that its games might not be available on it.
Players had all but lost interest in Steam's Big Picture mode after the Steam Machines faded into obscurity, and since Valve has already put in the work to program the Steam Deck's new UI it makes sense for the company to have that be the standard interface for TV-based Steam users going forward. There's no official word yet on when Big Picture mode is being replaced, but it's hard to imagine that it would be too much longer after the Steam Deck launches this December, if not before.
Source: PC Gamer, Steam Community Forum