15+ years in engineering here. 10+ in leadership.

Code formatting hasn't been an issue since the early '10s. Tabs or spaces? Who cares. Your editor can make it look like whatever you want and it won't effect the code.

As for other asshole-ish behavior or gatekeeping, I open it up to a vote. Let the team determine best practices. Don't like what your team decides? Find another team to shitlord over.

You must work in dreadful places. I've seen it a few times, but most places have been productive.

It needs a good lead dev to set the culture though.

Whitespace change debates can be avoided by using rule sets in IDEs and agreeing standards within the team.

Good static code analysis tools in pipelines and IDEs handle most technical issues leaving reviewers to focus on design, maintainability, clarity and readability.

You can avoid pickiness if you communicate why, so they learn and understand. If you use PRs as a training and learning tool they're quite productive. If not sure, ask why something was done.

And if you get picky comments respond with "personal preference and not part of team rules". But also, you cannot be defensive in your PRS. You have to be open to feedback and points and happy to discuss. Be polite even when feedback is invalid. Defendivesness kills constructive feedback and no matter how old you are and how long you've been doing it, you can still improve. Oh and if you been doing it that long, you're a senior or lead and can influence how things are done.