This isn't about making things public, just resistant to tampering and sniffing. Yes if you want to connect networks together then wireguard is a good choice.

This isn't about making things public, just resistant to tampering and sniffing. Yes if you want to connect networks together then wireguard is a good choice. If your devices are already on the same network and instead you close down the firewall and you move everything into wireguard you've just moved your problem.