Why are senior/experienced developers such bullies?

I have worked in web development for about 5 years now and every so often I find this type of person, which joins the team and remains really quiet for start, just trying to feel the ground and the team. They soon start talking about how experienced they are and how much they know, but in a very uncomfortable way. This is mostly noticeable in a situation when you have other opinion than they do – they talk about experience and win their goal using that.

They have possibly started job even after you have, but they come to the position for – what is feels like – one purpose only. To prove that they are better then every one else is.

And don't get me wrong – they know their stuff – they know design patterns, best practices, code paradigms, but they use it to show how good they are, and they do this mainly by pointing out other's mistakes.

After couple or more days of your hard work, you make a pull request. Before that you look it over it a few times to make sure it all looks good, all needed tests are written and it passes all linters and pipelines, and after – you share it with code reviewers.

Getting constructive feedback on you code is great. Overlooked mistakes, forgotten bits, possibility to make something differently or just getting a second opinion on how to build the module is awesome. But after making PR these individuals start looking at the code really thoroughly. If they are not able to find any actual mistakes, they focus on the style of writing. Like using for vs while etc. They put a lot of effort to check your PR and leave as many notes as possible. What make it harder is that they follow review up on a chat viewed by entire team, where they say that your feature can't really be merged and needs to be fully reworked as it doesn't meet basic standards. But they have just pointed out minor details. And they were not supposed to be reviewing the code in a first place too… but now they have done it, and person that was supposed to be reviewing the code mainly looks at their comments. It doesn't feel like constructive criticism at all.

I have received good comments on my work in the past. Also pointing out my mistakes and issues with the code, but I was really thankful for that as it helped me to grow as a developer.

The criticism I am getting here is more of a pointing out my lack of worth as a developer, while a meantime showing real worth of that guy who reviewed it. He is now waiting for another code being committed as this will be an opportunity for him to show his worth again.

Sometimes I start doubting myself – the guy is right after all. His comments are not incorrect, but I don't think that I should have any feel of lack of worth because of this.

Have you ever met such people in your team/surrounding. How did you deal with them? I would really appreciate any advice.