To be honest, the only way to stop the rot is to convince people never to embark on the ATPL training in the first place. Once you've spent the £100,000 you're unlikely to stop spending.
I still can't quite get over the fact that with terms and conditions on the slide so rapidly, herds and herds of people are still committing to pilot training. I'll readily admit I was very very lucky and got a jet job pretty much straight away on decent terms, type rating paid for etc and am now in a stable job on a good contract. However 7 years later I am still saddled with a huge debt and hopelessly unable to get a mortgage because of it, as I will be for several years yet. Did I really appreciate just how much debt I was taking on and the consequences? Probably not.
There needs to be greater education about the state of the industry and how it will eventually affect your chances of a mortgage/decent retirement income/decent lifestyle. These are the big issues which linger long after the thrill of setting TOGA for the first time has faded.
There's a temptation to think that you can just "do your time" in some crappy outfit before moving on to the bigger airlines. There are two problems with this. First, not everyone can possibly get a job with a 'proper' outfit - there are too many people trying. Some will continue to be shafted long term. Second, by "doing your time" you are effectively contributing to the downfall of your preferred future employer. P2F is just an extension of this and will eventually result in unpaid internships or worse.
There are plenty of people screaming about how great it is to be an airline pilot - namely the flying schools and the airlines themselves. Both keen to sell the profession to enthusiastic young boys and girls who they know will pay a fortune and work for very little. There are not nearly enough dissenting voices telling the true story - outside of these hallowed walls that is.