Hiding an IP and security are not necessarily the main use cases.

The tunneled reverse proxy aspect comes in handy when trying to expose internal apps on a network behind a hard NAT where ports can't be opened and a public IP address isn't available (like CGNAT).

Pangolin is also a VPN like Tailscale/Twingate/etc, so you can access non http resources via a direct connection via WireGuard and NAT traversal.