I think we can state as a truth that they have less potential profit.
That’s true but it’s not because people aren’t playing single player games. The reason single player games are less profitable is because the non-subscription, non-microtransaction single player market is extremely saturated with indie games. That makes it very hard to sell AAA single player games. The standards are extremely high and the opportunities for extra monetization are not there.
I have been a single player gamer for most of my life, yet I haven’t bought a AAA single player game in decades. I have more indie single player games to play than I know what to do with, and frankly they appeal to me more than AAA titles. Expensive graphics and voice acting don’t have much draw for me these days. I am much more interested in roguelikes and retro games now. I think there are thousands of others like me out there, among all those who don’t go in for multiplayer games and haven’t purchased a console.
Go into your watch history and delete all of the rage inducing videos. YouTube generates recommendations directly from your watch history (as well as subscriptions etc).
Then subscribe to channels you really like that don’t enrage you! I highly recommend hobby-focused and science-based channels. There are tons of them out there and they have great content!