100% this. I switched to Insync because as a developer, having exclude rules is HUGE (excluding node_modules and vendor folders).
Unfortunately, when I started syncing, I found out it's going very slowly. 2 files at the same time? It's gonna take ages. Seems to me like uploading multiple files is a very basic feature. Each of those 2 files are going painfully slow, and I still have almost 70.000 more.
Any word from Insync about this?