WhatsApp has already worked on a new feature, to restrict group participants and put them on Silence by Group Admin and we expect this feature to be public in next version update on App, Play stores.
The feature is un-earthed by WeBetaInfo, a company that works on exploring new, upcoming WhatsApp features. The idea is to give complete power to the group admin. Right now group admin can only KICK participants out of the group. In the upcoming update, this won’t be necessary as the admin can restrict a particular member and put them on Silence which means they won’t be able to participate/contribute in the chat (reply) and at the same time will stay in the group.
In this case, if all participants of a group are restricted, only admin will be able to send messages, maintaining complete control over the group chat. Everyone else will only be able to just read the messages.
The setting can be changed every 72 hours.