How do you deal with different development opinions and style in big organisation?

As a new joiner to the company that has over 100 software engineers, I'm struggling to understand how big organisations handle (if they handle at all) different style of each developer.

Surely you can do linting, but this will give you only some results.

What I mean is e.g. CQRS – some people like it, some don't. Some understand it, some don't. Some can use it, some don't.

Or more things like: use value objects or not. Do DDD or not. Use ORM or not. Use repository or not. And dozens of other smaller decisions.

Ultimately each team/microservice has its own style, architecture. Its own ways how STUFF IS DONE.

It would be ok, if things were done well, just with different style… The problem is that more often than not things are slowly evolving into another flavor of spaghetti.

Maybe it's normal? Just asking if things in FAANG (and other big tech) are enforced to be done according to certain way, or everything is done it's own way?