I’ve just seen far too many people express a sense of guilt about their unplayed games and an obligation to play them all. There’s also the “completionist” group who need to get every achievement in every game they have. Both are unhealthy IMO.
But yeah, I don’t see any negatives to the term “backlog,” provided you don’t intend to actually play all of them.
I personally do it because I get “analysis paralysis” where I just freeze up and don’t play anything if the list is too long. So I keep my “play next” list pretty short (like 10-20 games), which also forces me to be a bit more critical about my intentions to play a game.