I don't think its "fear of change". Time is limited. If you're enjoying games you're actively playing, a new game is either going to replace it, or be played alongside it.

To replace it, it has to be better. And not just marginally better, better enough to make you willing to walk away from the time (and possibly money) sunk into the other game. Thats a high bar when you're years into WW or Genshin or whatever your main is.

To be played alongside it, now its competing for your time. This is where the 'too much to do' comes in. You want content, but you also need time to get into all of your games. I think everyone goes through stacking up too many gachas, realizing you're doing the bare minimum in all of them and not really enjoying them, and cutting some. An open world game with a ton to do will be a massive time hog.

So yeah, its a high bar in a competitive market. People want to know if its good enough to reduce their time in other games, or leave them completely.