Don't take me argument as one against the point that it was massively popular and influential, en contraire, that's often the common factor in things I tend to dislike: the norm/ the mainstream.
It's mostly subjective when talking UI, and a lot plays in too regarding the lack of competive platforms with different UI's.
My point is that (I think) they became popular because of their UI and UX. They remagined how a small touch screen user experience could be most intuitive if you dont come with legacy mindset. For people used to keyboard and mice this might look weird but snap makes sense to the newer generation.
If all the other apps look similar its because they copied it. This is like calling Citizen Kane boring.
It's mostly subjective when talking UI, and a lot plays in too regarding the lack of competive platforms with different UI's.