I took writing courses or workshops as a way to spend my vacation time from Day Job with fellow writers. Sometimes I ended up being the only novelist in a bunch of poets, sometimes it was overcrowded, sometimes it was just fine.
I met people (although, like you, I’d rather be a hermit) and learned something, yeah. My next workshop is on Indie Publishing, I have enough of “how to write” courses! 😉
Never tried the online ones…