I've never really used Adobe's file syncing before, but I downloaded Premiere Rush and it seems to want to put everything in the cloud. Okay, fine, I'll give it a try.
Well, every time I let it try and sync, my Mac crawls to a halt and I finally end up with the rainbow beach ball and have to shut my system down to get it to work again.
I'm on a 2010 Mac Pro running 10.13.6.
I have no problems using Dropbox or iCloud syncing. They just hum along in the background, even if it takes time for them to sync. I'm in a rural area and use a radio-based internet connection, so my upload speeds aren't great and there are times the signal varies a great deal (weather, etc.). As I said, I never used Adobe's syncing before now, but it appears to be unusable.