Idk about that...a lot of people who leave Android for iOS usually stick to it. I did say a lot, so there are people who go back to android. I was an iPhone user then android then iPhone and tried to go to the pixel 2 but returned to my iPhone X. To me iOS is just so cohesive (iMessage and FaceTime) and the form factor of the X is like no other device. The OLED screen is quite impressive and yeah iOS may be boring but the phone is pretty stellar. I think once android users who switch see how well iOS performs, they then start using the saying “it just works!”
For me it is just those damn notifications. I can't stand them on iOS. If that got fixed that would my biggest gripe (a few small ones would still exist but nothing game breaking).