They don't plan to recall them. Collectors love errors mainly because they're rare. There's 480 million of these and they'll never be worth much more than 50 AUD.
As someone has already stated, they recycle these notes as well. Even though they're plastic, they won't last forever. It doesn't help they're high denomination and therefore less used, but I wouldn't be surprised that after about 50 years, there will be a lot less of these.
They'll be even more rare in an un-circulated state.
With inflation, they'll be worth less than 50 AUD. :)
Even with inflation, they'll be worth 50 AUD. But you won't be able to buy as much with it.
50 AUD is always 50 AUD, but it's not necessarily worth the same amount of burgers