John Smith - horses for courses. Just because you don't like it it doesn't mean someone else will dislike it too. Maybe you just chose the wrong profession.
Does your son want to go to University? Bearing in mind that university applications are up 22% this year and fees are destined to rise, maybe you would want to minimise your debt if he is 100% locked onto flying for a living.
If that is the case, make sure he gets his A Levels. At 16-18 you're best off in the security of college/6th form.
Suggest to him that he works for a few years before starting training, no one needs to start at the age of 18. Don't let him sign up to debt, don't go integrated. You can easily do your training in credit if you really plan well.
Yes, flying isn't what it used to be. However he was never there to see what it was like before so he won't feel like he's missed out.
Good luck,