> C++ is also surprisingly good, but you pretty much have to tell the LLMs to treat it like Go and don't use any of the dangerous features for normal code.

For existing codebases I made the experience, that LLMs are very good at replicating their style.

At work most of our C++ codebases use a fairly consistent style and subset of C++ features and to my initial surprise specifying style conventions etc explicitly turned out to be mostly superfluous.

Of course, we also have some legacy projects originally, written in ANSI C, which only received a few changes in the last 15 years to compile with a C++ compiler. Here a style guide is helpful, bit I consider it more like a temporary instruction for refactoring.