They would not need to be heard to seek recognition.
A rule could be adopted, in an in person meeting, that to seek recognition, a member must hold up a certain colored and/or shaped card. Once the card is raised, the chair recognizes the member. The member then states the motion. That would not change the characteristic of this as a deliberative assembly.
In this case, their appears to a de facto rule, that if a member wishes recognition, he signals by typing an emoji. He is then recognized and speaks. That does not change the deliberative assembly characteristic.