Also, of course, the majority of SaaS apps (perhaps most apps in general?) are not compute-bound, so gains from performance alone shouldn’t be the only metric.

My current job has a mix of Python and Go. Personally, I dislike Go. I don’t like its syntax, I don’t like its utter lack of formatting standards (gofmt is not a standard; also it sets tabs - ugh), I don’t like its insistence on static linking, and I don’t like how people claim it’s a great scripting language when you can’t just run a file on its own (and its stdlib is weak sauce compared to Python).