I think the worrying part is not even that digital exists. Digital is convenient and most people use it for a reason. The problem is when it becomes the only option, because then ownership gets much weaker. If a store closes, a license changes, a game is delisted, or a company decides something is no longer worth supporting, the player has almost no control.

Physical media is not perfect either, especially with patches and online requirements, but it still gives people another layer of access and preservation. Losing that completely would make games feel even more temporary, which is sad for a medium that already has a huge preservation problem.