How to defend Aisha's marriage age?

If we take the usual view that she married at 6 and then later consummated at 9 after her menses and the Prophet (saw) was in his early 50s we can challenge the non Muslim critic by saying why do we not have a single report from the enemies questioning her "young" age and his "older" age? And do you think her parents would let her marry so young if in their culture it was not normal? The scholars who say she was older and in her late teens use the fact that the reason we have no reports from his enemies is simply because she was never married so young and the Hadith reports missed a 1 so it was 16 and 19.... Now when you tell the critics all this they still do not agree and say if Muhammad (saws) is the perfect man for all times then why do some Muslims give their daughters away for marriage at similar ages as 9 (child brides) even today? How do we answer this? Who said these Muslims are right? Even if some scholars today allow it not all scholars are fallible. Even if it is done today it could be in regions of the world which aren't modern by our standards and live in the desert and the children don't go through school college university job routine... So marry young. Please comment and add thought.