The only things I would consider: what do you love to build?
After a lot of web and APIs dev (NodeJS, Go, Rust, VueJS) I'm now building the native apps of my project (https://bloom.sh).
I find mobile development (especially iOS) very frustrating, the ecosystems are really closed and platforms are not focused on empowering developers but growing their profits and closing more and more their walled garden.
The only 2 reasons I've not abandoned mobile development are:
1) Flutter, a fresh air in UI development, whether it be the simplicity, the tools or the ecosystem.
2) the possibility to build offline first apps.