I find tech leads to be the most difficult people in any organization to work with (always with exceptions), I think it’s because they are still learning the lead part, and at the same time are trying to prove themselves.

Coming in with a hexagonal overhaul is a great example. At least in this case it seems the writer didn’t dig his heals in too much.

I think it's also that they have a vision and unfortunately this means they have to say no to landing PRs that don't make sense to the overall vision often. And nobody likes to throw away work.