Because standardization matters and the first thing to become the standard is extremely difficult to unseat.

But some of types of things have in fact changed, sometimes for seemingly trivial reasons.

For example, the master/main branch shift. Everything broke when that change was made, but it happened and it wasn't a big deal.

I'm not seeing the difficulty here. It seems that a more reasonable interpretation is that git has the type of interface that is hard to learn, but intuitive once learned.

The master/main shift was fueled by political correctness. If “master” wasn't a synonym of a word associated with slavery, it would've never happened.