For me it’s Whatsapp. Like 99% of people i know use it so yeh… i still need it. I am considering moving the Whatsapp Gdrive backup to a local backup btw.
Google photos is also a major problem for us. We have a lot of stuff that want to migrate to different service (or store locally).
We are moving in different circles then, because my Millenials and Zoomers are very much on Signal, or even more nieche stuff. Meanwhile anyone over 45 seems to be glued to all the Google, Meta and Microsoft products.
Same experience for me.