For me, as someone who played OW just to have fun, what pushed me away was just the lack of things to do. No mode diversity meant stuff got stale really fast.

Remember OW was supposed to be a different game, one that they cancelled. They reused a lot of the assets and so on and hashed them together with the ultra-popular genre of the time. It mostly worked at the start but it was pretty clear to me after a little while that they didn't really have any clear idea about where to take it. It always felt like a "recovery" game, a "we spent a huge sum of money building these assets, let's at least get something out of them" rather than something with a well-thought out long term plan behind it.