Super slow connection with tailscale-enabled client, when router is set to route through vpn

I have a wireguard set up on my openwrt router, so that all traffic goes to the wireguard interface, not towards wan. this makes every device on my network protected from prying eyes. I came across a issue though with using tailscale. tailscale is using wireguard itself and when i use it as exit node, the connection is literary a 10th of what it originally was. when i disable tailscale on the device, everything works in full speed again. I wonder if i can do anything on the openwrt router to prevent these huge slowdowns, note that when doing a speedtest connected to the router with wireguard enabled, i get the same speeds as without. Only through the tailscale exit node, i get these super slow speeds.

I am first of all hoping there is a way to improve these speeds, something is clearly interfering here. But if not, i am wondering how tailscale on the router functions, that i could try as a installation. Can i then also force all traffic to flow through the wireguard vpn interface on the router, while keeping access to lan ip’s anywhere i go?

Thanks!

I cannot understand your network topology by just reading the text.

So where is the exit node? Do your TailScale have direct connection? If it goes through TS server then it will be slow.

The exit node is at home, connected to a router that runs mullvad vpn on wireguard.