NetworkManager unresponsive with wireguard VPN-Proxy setup

I’ve got a problem with NetworkManager hanging while trying to interact with it.

This only happens if my wireguard vpn profile (in NM) is active, not all the time. Its a proxy VPN that provides the default route with a lower metric than dhcp routers.

I got logspam about the ip6 routing table being too small but I have increased the limit already.

Usually it did work fine and wireguard didnt interfere with changing wifi underneath. The wireguard profile is set to autoconnect, not as dependency of another profile and is even listed as “active” when no other network is connected.

Setup: Fedora 34, Gnome (unwillingly), dual iwlwifi only one managed by NM, macrandomization on, using Gnome Settings, nm-connection-editor and nmcli to interact with NM.

Do I have wrong assumptions there / can you help me?