I see your point, but the syntax inside of fstrings forms an entirely new sub-language (DSL). I can look at old python and know exactly how the .format() calls parse with positional and named keyword arguments, but looking at the fstrings I need to be familiar with all of the new magic.

I've heard similar complaints about the loop macro in Common Lisp, and this feels a bit like shell or Tcl strings which could mean anything (arguments to sed/awk or paths to widgets/urls). However, I guess people are familiar with regular expressions as a completely foreign nested language (DSL), so this isn't much different than that.