I’m not sure if that would have the desirable result. Using sockpuppets to circumvent a ban will lead to the ban of the sock as well. There is a user who once created hundreds of sockpuppets. Sometimes I would discover a new one almost every day. It got quite tiresome keeping track of them all the time.
Also the permissions system isn’t fine-grained enough yet to block specific features (except writing edit notes or editing and voting altogether)
Before any sanctions are applied people should try to speak to each other. Preferably directly (in fact, I just sent them a message).
If that fails someone higher-up can be involved. This would be the current community manager Freso