"Australians have a terrible sense of humour & are appalling at comedy."
I would have to agree with you that what passes for comedy on HC and the current genre of "comedians" is unrepresentative of what comedy should and used to be, however the problem is not confined to Australia. Posting "insert target Country here" memes and whinging about something you obviously don't understand gives you no credit.
The septics are the ones who have no understanding of comedy, and the current Americanisation of society is probably the main reason for the decline here and elsewhere. Post war, the poms gave us the likes of Peter Sellers, Eric Sykes, Jimmy Edwards, Tommy Cooper, John Cleese, Michael Palin, Peter Cook, Ronnie Barker, Benny Hill, their accomplices, and doubtless others I have missed, but seem incapable of replacing them.
Miriam Margoyles summed up pretty well with her observation that Barry Humphreys had more comedy in his little finger than the entire Melbourne Comedy Festival; he obviously went some way towards filling the void in the UK.
