justified in being irritated by composer install for CI4?

Not sure I understand what issue you have with this.  This seems correct to me.  Your "project" psr-4 autoloads the CI4 system libs which are located in vendor/coneigniter4/framework/system.  You can ignore the "app" in vendor/codeigniter4/framework.

Generally, I pretty much just ignore everything in 'vendor' as everything I need should get autoloaded from there anyway. So it's something I do not even really think about.

See attached screenshot.



https://ibb.co/bBLNkht