Interesting, I went the other way about 7 years ago - switched from fish to zsh (initially with oh-my-zsh). The interactive experience was similar enough on both shells, and the performance was great on fish and okay-ish on zsh, but two things won me over:
1. With zsh, I can copy-paste some bash snippet and in 99% of cases it will just work. Aside of copy-pasting from StackExchange, I also know a lot of bash syntax by heart by now, and can write some clever one-liners. With zsh, I didn't need to learn everything from scratch. (I guess this matters less now that you can ask AI to convert a bash one-liner into fish one-liner?)
2. For standalone scripts... well, I think it's best to reach for a proper programming language (e.g. Python) instead of any shell language, but if I had to use one, I would pick bash. Sure, it has many footguns, but I know them pretty well. And fish language is also not ideal - e.g. IIRC it doesn't have an equivalent of `set -e`, you have to add `; or return 1` to each line.
1. With zsh, I can copy-paste some bash snippet and in 99% of cases it will just work. Aside of copy-pasting from StackExchange, I also know a lot of bash syntax by heart by now, and can write some clever one-liners. With zsh, I didn't need to learn everything from scratch. (I guess this matters less now that you can ask AI to convert a bash one-liner into fish one-liner?)
2. For standalone scripts... well, I think it's best to reach for a proper programming language (e.g. Python) instead of any shell language, but if I had to use one, I would pick bash. Sure, it has many footguns, but I know them pretty well. And fish language is also not ideal - e.g. IIRC it doesn't have an equivalent of `set -e`, you have to add `; or return 1` to each line.