Earlier quoted context omitted.
Our experience has been yarn is fast and reliable.
Hmm, `yarn add` reliably takes a few years in my environment (WSL). Maybe the environment is the problem, though.
The reason it's so slow is because the virus scanner is running on the insane amount of tiny files a typical JS app will have. Used to take me 30 minutes each time until I did that; it was still slower than Linux/Mac but it was coffee-break slow, not three-course meal slow.