I dont think its a case of being better at an accent, or indeed being better at performing your national culture. Maybe you are being over-competitive in this area, part of the Australian in you, perhaps?

There are plently of mainly 'English' sessions going on where I live, as well as mainly Irish & Northumbrian, mainly Acoustic and other sessions. It is not the case that the Irish session is threatening to take over the English one, or anything like that, they co-exist happily. Can you see a problem with this? If all the sessions became 'English only' then would you be happier, and if so would you be happy with the loss of variation? Why?