Because Zwift isn’t outdoor riding. Keep Together meetups are a great feature and used extensively by my club.
Instead of splitting into multiple groups (like outdoors), everyone can enjoy being in the same ride, no matter their ability. This makes it very social and inclusive. It also allows everyone to have as hard or as easy a session as they want, while being kept together on the road.
Calling for a feature with lots of benefits to be dropped just because of a bug causing a side effect to a third-party service doesn’t make any sense.
It’s a bug. Zwift should fix the bug.