It seems to me that the requirements for personal infrastructure and professional service-grade infrastructure have drifted so far apart that essentially, if you know one world you don't (automatically) know the other at all.

Tbh, I have no real world experience in this, so it might just be my own delusion. However, I've recently started getting into self-hosting some of the services I use. I'm using a simpler infrastructure than what OP described and while it is the right choice for me and a useful skill to have, I feel like it absolutely won't get me anything in the sysadmin/ops/etc. job space. I've actually considered adding more "enterprisey" tech to it (like Ansible or comparable stuff) just to make it more sexy for recruiters.