I've written parsers and compilers, worked on image processing software for the NASA Mars rovers, managed global Kubernetes deployments for Fortune 500 companies, wrote trading desk software used on the NYSE trading floor, etc. Point being, I've worked on some seriously complex software. I'm 100% sure I could write Git itself without any trouble whatsoever (assuming I learned how it worked first).
I find Git to be unintuitive and overly-complex, and to use terminology that isn't obvious. You're probably right about it being an internal objection, but I assure you it's not due to laziness or an inability to deal with complexity. I'm not planning to use jj, because it's just Git with more complexity layered on top, despite their claims to the contrary.
Despite my dislike of Git, I'm still the go-to person for Git issues on the teams I manage. I can fix problems that arise and help others do things right. I still don't like it, and for whatever reason, the edge case scenarios don't stick in my memory.