Yes this is a real problem. I was lucky in that the school where I got my Certificate in the Foxbat also had at the time a Drifter. Once I had completed my navs etc and checked out on the other aircraft, (Jabirus J160 and J230) I simply had to move onto the Drifter. This was a great aircraft as it gave me Tailwheel, Low Power, and 2 stroke. Sadly I was the last person to qualify on that aircraft before it was sold and not replaced. I suppose the fact that I probably put 20 of the last 25 hours on it meant that it was not worth the cost of maintaining. Especially when I purchased my own plane so was not flying it any more.
The simple reality is if people do not want to fly these types of aircraft anymore then it is not viable to the flying schools to keep them. If a drifter within an hours drive of Brisbane is not being used, then I fear that these types of aircraft a doomed to a small group of enthusiasts and the newer more modern aircraft will be the future of Rec Aviation.