Every strata manager in every state/territory in which I have been a strata owner has been given the right to run most of the OC/BC functions. This includes some of the largest strata management firms in Australia. It is a delegation of authority usually done at each AGM.
Included in that delegation of authority is the authority to call and conduct AGMs.
Even as an OC chair I’ve rarely been consulted by a SM about the AGM except for perhaps setting the date and location.
To be honest I don’t think it’s so important. An active strata committee has very many other options in the general running of an OC/BC.