It sounds to me like the committee just got spooked by someone putting the fear of god into them that the gym area presented all sorts of immediately catastrophic liability risks.
So, they issued some rules that they thought would get them out of this situation but they didn’t put them to a meeting for the entire owners corporation to decide. Probably correctly, they thought this would be too hard because only 25% opposing would vote it down and oppositions are always more motivated and organised. Also, their imagined huge liability risks (there are some and there would be reasonable ways the deal with them, but they are probably catastrophising) would remain until they had managed to organised a general meeting and explained their case, and their case probably did not amount to more than anxiety rather than a reasonable assessment of the risks.
So, since they made up these rules, and since they are getting some pushback from you, they have decided they can soften a little in the hope that you will go away. They probably have good intentions but not the energy to do it all properly.