One would hope that it is “normal strata procedure”; particularly in the case of those who demonstrate gross disregard or pig ignorance of the affect of their actions on other occupiers. In fact it would be much better if they used terms such as “we’ve become aware” or if they have clear evidence “a recent inspection has revealed”. This would provide protection in cases where it may be obvious to perpetrators that there is only one individual in the block with the sensitivity and wherewithal to contact the Strata Mgr.
There appear to be many blocks where occupiers in locations where there is a very understandable desire for further privacy put up flimsy “brush” style barriers which are soon blow into various angles; add some washing and a bit of “junk” storage and even a new block gradually takes on an (expensive) slum like appearance.
You seem to have the good fortune to have someone who cares either about the aesthetics or perhaps has no objection to your efforts but want’s to maintain a rules based system rather than anarchy. Or more likely someone who generally cares about neither but have a vague idea that anything out of the ordinary will negatively affect their property values.
Why not try the system out an put in an agenda item to modify you balcony; perhaps including a few options and the usual acceptance that it will be done in a workmanlike manner; you will pay for any maintenance etc. Failing that; I’ve never heard of any rule about what you can have on the balcony apart from washing; there are planter boxes which sit on the top rail and ferns etc. would rise 60cm or so above that – although again the legal terminology “not in keeping with the appearance of…” could mean anything on a balcony.