>If you read the forums or subreddit you'll see people claim to enjoy Portal mode, but also say things like "what's the point in playing Portal if you can't earn XP". It's an attitude I don't understand at all - the point in playing Portal is that it's a lot of fun! But most of the community seems to disagree with me and as a result Portal mode is empty.
I have a strong preference for rougelites over rougelikes because the former includes a meta-game progression. It includes a sort of XP that makes me enjoy the game loop more, even though the fun from the actual game loop would in theory be equal regardless of some sort of meta-progression.
I also enjoy fighting games with RPG mechanics over those without, once again because there is a meta progression system. It isn't just a matter of getting better, because you'll end up facing harder enemies who also are now better and the skill doesn't change.
I think these concepts are related to what you mention. Even RPGs in general have this sort of progression across a long span of playing that adds value to a game beyond what the minute to minute gameplay offers, despite enemies getting stronger and the net gameplay not really changing. When I play Diablo style ARPGs, same thing. I get stronger, but so do the enemies, and the gameplay remains much the same but I wouldn't play the game if it didn't have what I'll call potentially pointless progression.
I also think it is interesting to measure potentially pointless progression that becomes so pointless it harms player experience. Possible examples, and I say possible because the threshold changes per person, are Elder Scrolls games, especially Oblivion, and FF VIII. Both games are some flavor of RPG where enemies get stronger as you get stronger. Not enemies in new locations and often not even new enemies. You level up, the enemy you were just fighting also have gotten stronger. With a good build and knowing the system you can ensure your own level curve is higher and thus a real power difference happens that matches more classical RPGs, but it is also possible for those not min maxing to become overpowered by enemies. This factors into my fun even though it has little direct impact on my minute by minute gameplay (at least until one side really overpowers the other).
Video games have always had this sort of progression that increased fun despite not looking like it adds to the fun during the minute by minute gameplay. What has happened is that developers have found ways to tie these mechanics to other factors that can then be optimized, generally for the purpose of making money, though sometimes you see developers optimizing engagement for the sake of engagement. This sort of optimization can end up running counter to the minute by minute gameplay. Progression becomes so important that people sacrifice enjoyment of the gameplay so they can get enjoyment of the potentially pointless progression. While grinding isn't new, there was almost always some other gameplay as the goal. Now that has changed to grinding just for the sake of more grinding. In the past that would have been the sign of a bad game and people would not engage if there was no end payoff, but these days it has been optimized to just the right level to replace fun with compulsion.
It makes one wonder what is the ultimate game. Imagine a game that you plug in and then it fills the TV with light patterns that activate all your pleasure centers like some cyberpunk electronic drug. Is that the future down the path we are currently going? Was that always what was waiting us at the end of the path of entertainment even before video games existed?