As the product of a four week game jam between two friendly studios looking to experiment, Peak was never intended to be an overnight viral phenomenon. Thus, co-developers Aggro Crab and Landfall also didn't have plans to support the co-op climbing game in perpetuity, like a live service title, and over 10 million copies sold isn't changing that fact.
Aggro Crab (developer behind Going Under and Another Crab's Treasure) studio head Nick Kaman said as much in an interview with GamesRadar+, where he explained that updates for Peak won't last forever. For context, both studios have been non-stop supporting the game since its viral launch, most recently with a wintery holiday event featuring snowball fights.
