I don't understand why in this full node distros, connecting through tor is the default.

Besides the fact that lately tor has been getting constantly ddosed, it is not the best way imo to connect to your own node.

A wireguard bridge is ridiculously easy to setup and allows you to connect to your electrs, lnd, etc without you having to worry about tor, onion addresses, domain names, certs, etc.

Just plain http across an encrypted wireguard tunnel works. It's private and secure.

Is is anonymous? That question does not even make sense. Even if all your encrypted communications are being monitored, is it really a secret that you are connecting to your home IP address? No much anonymity lost.