Why not help everyone out by allowing anyone to connect?
Beacuse of traffic limit.
Maby limiting number of connections and connection speed for the rest world helps?
Bitcoin core had a maximum number of connecting it can have. it's only allowed 8 outgoing connections and 255 total connections by default. You can of course change the maximum total connections to be higher or lower, so you don't need to block a bunch of people from connecting to you.
And limiting the connections and does does not help everyone else. It increases latency which is not very helpful.