My point is that POSIX shell purity is masochism. Understanding how it's the core and other shells build on top of it is certainly valuable, but it's not inherently particularly good to use.
If you are talking about interactive use, of course bash is the one to use, but for writing shell scripts, it is a 10X interactivity overhead" over dash.
The amount of gyrations I go through to account for the lack of arrays is easily 1000x worse than accounting for not having local variables.