

The easiest solution if you want to have managed VMs IMHO is to just make a large VM for all your docker stuff on Proxmox and then you get the best of both worlds.
Abstracting docker into its own VM isn’t going to add THAT much overhead, and the convenience of Proxmox for management of the other VMs will make that situation much easier.
LXC for docker can be made to work, but it’s fiddly and it probably won’t gain you much in the long run.
Now, all these other issues you seem to be having with the Proxmox host itself; are you sure you have networking set up correctly, etc? curl should be working no problem; I’m not sure what’s going on there.
The rights holder is seeding and records your IP address, then sends a C&D to your ISP, who then notify you about it.