could it be your isp throttling your connection?, try downloading a file via http and see what speeds you hit, also you could try connecting to a different PIA endpoint and see if that helps.
I think I fixed my issue. Uninstalling DelugeVPN, turning off the docker service, rebooting the machine, enabling the docker service, and reinstalling the app fixed my speeds. Back up to 10 megabytes/sec. I still have no idea what was going wrong.