I moved to ZSH some years ago but even that is not good enough. I thought of using Fish at one point but just said "frak this" and started writing Golang for anything that's more than 20-30 lines of bash/zsh scripting. Or requires their weird list / array syntaxes for iterating over stuff. Can't ever remember that with a gun to my head.
That's the contention point though -- I learned and relearned shell scripting no less than 7 separate times and it always slips away because it's not something I practice every day. Ultimately I concluded it's not worth it because you mostly have to memorize super weird syntax and strange exceptions to rules. At one point I was just like "screw this" and went for Golang.
> You are not gonna get the same performance with just or whatever new tooling there is just to run commands on your system
That's very debatable, I'd bet my Go programs process various things either faster or with the same speed. But even if they are slower that's often not important because most scripts I ever wrote were throwaway. Those that stuck around I have polished and re-polished, including with the measures you enumerated.
That’s a big if. I worked on a shell based tool for a couple years and eventually accumulated the know-how and toolset to write reliable code; but nobody else could contribute as the learning curve was too great.
I switched to Ruby for all new tools and never looked back. Performance is rarely a concern in this territory, and you can always offload heavy work to another process.