Personally, I find brace style wars utterly uninteresting, like most other coding wars. The only thing I get evangelical about is inconsistency. I don’t ‘despise’ whatever style a project uses, so long as they are consistent and clear.
I don’t think I have had anyone go so far as to call another person’s whitespace and brace preferences ‘unprofessional’. The only thing that’s unprofessional is refusing to use the style guidelines for your current project. Each project gets to decide what ‘professional’ style means in their codebase.
All of the C-style languages, as far as I know, can use any of the main brace styles. You can write C# with Allman, K&R, 1TBS, Horstmann, GNU, or whatever you like. It really doesn’t matter. Same goes for C, C++, JavaScript, etc. There is nothing to ‘fix’. Whitespace does not have syntactic meaning in C-style languages on purpose. If you want whitespace to have meaning, look at other languages, like Python.
I personally prefer 1TBS. It seems to me be readable and not generate superfluous lines only for opening braces, and it seems to be the most common style I’ve run across. I’ve also worked in codebases that use Allman without complaint. It’s not my favorite, but it is fine. I just use the formatter to make sure that my code meets the standards of the project I’m working on.