I've been using fish for nearly 10 years.

First, there are some ways to make fish more compatible with bash.

If you want to do some shell scripting in fish, or running other people's shell scripts (or commands) this may aid you since you wouldn't have to port them (or take less time to port them over).

You can achieve this with a plugin system such as 'oh my fish' or 'fisher'. But, as always, it adds complexity (and bloat :P), you'll need it on every fish shell (including remote systems), etc.

It is a bit akin to having nvim with plugins versus being able to use vi. Sometimes, you're going to need to be able to use the latter.

Also, to people who recently adopted fish: fish has been made more and more compatible with bash throughout those years.

FWIW, I use fish with starship these days.