In the UK, lots of flying schools advertise PPL cost being about £5-9K depending on location in the country and type of plane -- that's just for instructed flight time (i.e. 45 hours). That gives you a UK minimum. Realistically in the UK, it's probably averaging about £10K all in, plus or minus depending on factors, of which flight time cost is the highest. I say this having recently qualified (mine was £15K on a PA28 in 60 hours with generous personal equipment expenditure) and done the research on it, and talked to other students about their experiences. 22K AUD is about 10K GBP. Your flight time cost of about 400 AUD per hour is about 200 GBP per hour which seems consistent with UK prices. From some recent research into flying in Australia, I think the costs between Australia and UK and roughly equivalent, probably on the upper end globally.
Flight time cost seems largely a factor of fuel cost (a standard PA28 161 training aircraft chews 30+ litres per hour, being about £60 per hour in the UK) and a pro-rata maintenance cost (high in the UK under EASA, with 50hr/100hr checks, etc). Plus you have an instructor cost, £50 per hour at my school. So to lower your flight time cost, find a country with lower fuel prices, less expensive maintenance, and lower wage/living/etc costs lowering instructor costs. That's not the UK, and it's not Australia
.
Students should have a realistic budget with contingency otherwise they will risk stopping/starting training, which extends the hours required (too much "getting back up to speed") and the churn across instructors (too much repeating some things with new instructors) and the risk of lapsing exams. I've spoken to a number of students where this has happened.