Funny, I think we've had a very similar discussion previously. One of the elements you're failing to account for is pretty simple: Multiplayer.

All games are to some extent repetitive; games are in large part, even if voluntarily, constrained by genre. The "least repetitive" game would be an absolute chaotic mess spanning multiple genres...and probably not very fun.

For context, I personally don't even play any of the games you mentioned, but I've played plenty of other very repetitive games; MOBAs, shooters, ARPGs...even turn-based tactics could be considered repetitive. Again, most games have a very straightforward gameplay loop.

For things like MOBAs and shooters, the fun and challenge comes from the other players. The gameplay itself might be repetitive, but the fact that you're up against other people, and can actually lose (which is pretty absent in most at least modern singleplayer games, outside of roguelikes/lites) is what keeps things interesting.

It's like asking why people could play so much chess. It's not the raw gameplay itself, it's the fight and the ability to improve your skills and overcome.