Surely people have found patterns that work reasonably well, and it's not "everyone is completely on their own"? I get that the scene is changing fast, but that's ridiculous.
You can do that in conjunction with trying things other people report, but you'll learn more quickly from your own experiments. It's not like prompting a coding agent is expensive or time consuming, for the most part.
But your codebase is unique. Slop in one codebase is very dangerous in another.