Assuming that the cats arrived on the scene AFTER the by-law was registered, the worst thing the strata committee has done was to officially make and minute a decision to defy their own by-laws.
The smart thing to have done would have been to have a quiet word with the owners and tell them not to worry.
By putting this on the minutes they have left it open to any owner who objects to pets to take the SC to NCAT and challenge their decision, which could theoretically lead to the cats being evicted.
There are certain fundamentals in strata law, and one of them is that strata committees can’t change or override by-laws. They have to have a general meeting and get 75 percent of the vote to do so.
There’s something else worth noting here. There is a ratchet effect with by-laws.
If you blunder into by-laws on a “suck it and see” basis, you can find that badly thought-through rules can be very burdensome when the 25 percent of owners who bullied everyone else into accepting them refuse to change them when they don’t work out.