Pangolin is "public ingress to private networks" and not a mesh VPN/network builder. As you say I think NetBird is an alternative to Tailscale and we are an alternative to Cloudflare tunnels, Ngrok, or Zscaler. It is more about exposing things publicly with authentication in the browser for people to access than about building a network for disparate devices to communicate.
It is correct that pangolin is something like pinggy.io or cf tunnels as you mention. But those do not give such fine grained access control it seems - like a firewall checking identity and all.
But definitely it is not a vpn or mesh network it seems.
I am personally a user of NetBird and love it.
The design of the UI is very similar though :)