There's a difference between consistent code style and forced language conventions.

Also, I'm not sure you'll be able to convince me that reading "public" and "private" add meaningful cognitive load to reading code.

Right, the difference is that the former isn’t real. When you have millions to billions of LoC developed by thousands to hundreds of thousands of developers anything not forced isn’t going to be consistent.

You can enforce code style through linting and CI. In some projects I've worked on, code doesn't get merged if it doesn't pass code style checks.