If you want a hard-to-use VPN with minimal features and minimal surface area, as you said, Wireguard is right there. Tailscale is convenient Wireguard.
I use Wireguard for several site-to-site VPNs. It just works. I never have to worry about it, and there are very few configuration settings to mess up (unlike, say, IPsec, which is a nightmare.)
I use Wireguard for several site-to-site VPNs. It just works. I never have to worry about it, and there are very few configuration settings to mess up (unlike, say, IPsec, which is a nightmare.)