For ten years, I worked on codebases written in C++ without using any third party libraries (no, not even STL -- we needed faster, thread safe versions of strings and maps which were not available at the time; Boost? What's that?), its own custom messaging middleware built directly on sockets, its on distributed process management system built with unix syscalls (obviously). There was not a single line of HTML, Java…
So you left a job that paid 2x and exposed you to hard problems that require reliable solutions for a job inside the horror clusterfuck that's the modern web where nothing really "works" and there's no real engineering to speak of besides monkeys throwing crap in a shared pile and shovelling it out the door ASAP. Good for you I guess?
Even if the decision he made was a bad one, you don't know anything about why it made sense for him at the time.
People aren't algorithms running in complete isolation and silence. They live in nuanced circumstances you can't possibly understand by his short history in a comment.
I hope you can find understanding and peace in the future.