They mentioned "20 ways of doing things", I'm replying to that complaint.
Quoting is an issue if you don't understand the IFS and command expansion. It's an old fashioned style, but it is consistent and there's only one way of doing it (quoting every variable and subshell use).
Think of shell variables as non first-class citizens, they can only be used interpolated within a string, like "$var". The shellcheck tool enforces this perspective, which makes ' and " behave very much like python or JS.
