There is a great talk by their C++ dev team about how a build everything from source, mono repo really helps with C++ change enablement

https://m.youtube.com/watch?v=tISy7EJQPzI&t=2589s

Personally, I’d have to agree that at a minimum a mono repo per distinct product role (server side in one mono repo, desktop software in one mono repo) is immensely valuable.