Far out, if the indigenous want to have smoking ceremonies and welcome to country, whether it was invented last week or 40,000 years ago, let them. If there’s one thing this thread has highlighted, there’s a lot of people with little tolerance, and there’s just as many who think we need to hand everything over to apologise for the last 230 years!
Why don’t we just all get along and treat each other equally. Look forwards in writing our future, while acknowledging our past. But don’t let the past write the future.
As for the flag, we have one currently, it’s called the Australian flag. If everyone (or the majority) feels strongly about adopting another one which acknowledges all parts of our society, then make the noises in the right places.