For me the issue with Mullvad is like this… I connect to a server, I get good speeds, but after an hour or two, I get stuck at 2-3mbps. This issue gets resolved when I reconnect, even to the same server. Also, I like using OpenVPN over TCP, but their speeds, in Mullvad’s case, are terrible for all exit nodes.

It also may be the case that my ISP is deliberately ruining the IPv4 routes because I am connecting to a VPN for privacy.