Having lived in Hong Kong where many balconies are netted for child safety I think it is time that properly tested, approved and installed netting was exempt from needing strata approval provided it is unobtrusive which it was in the buildings I lived in.
Many apartments these days have large balconies with furniture on them set up for entertaining so that keeping children off the balcony is unfeasable at times. While off course the children are supervised if a plant pot or lounge chair is close to the rail an accident can happen even with a parent there.
Another solution I saw in Hong Kong was to add a higher temporary railing to the inside of the balcony rail using an expandable system like the security barriers used to shut off areas by security staff. This had the benefil that it was removable and so only used when entertaing on the balcony. The owners corporations may find this more acceptable than netting. They are not chaep but they are moveable so can be sold when no longer needed.