Avram > the shul did not actively throw anyone out who wasn’t wearing a mask,
If this was pre-vaccine and there were older people in the shul, the question would be how big the shul was. If it is a huge hall with enough place for people to separate, this would be fine. If it is “6 ft” theoretically, but 3 in practice – in 1 dimension, with people being close together, then it was not responsible at that time.