I’ve been using linux off and on for almost 20 years, though only did a full transition to linux for everything about two years ago. I use debian for the servers in my homelab and Fedora on all my other computers.
Something tells me this chart is based on an external assessment of competence/confidence not a self-assessment, because according to the chart I should be a guru, but in actuality I know nothing.
Isn’t the list of shells that are “not fully POSIX compliant” basically every shell in modern use aside from sh?