I would counter your suggestion that CTC's cadets are sponsored; they are not. The responsibility for the costs of training at CTC rests with the student, not with an airline. Successful students who achieve a position with some of the airlines CTC supply may find that some of their costs are covered (or at least deferred) by their employer, but that is not guaranteed - nor is any job at the end of training. Should a cadet fail the course, again, the financial responsibility rests with him, not with his target airline. That, to me, is not sponsorship.
Sponsorship is what the military does, and BA used to: accepting all of the costs and all of the risks of training, including failure, while paying the student (an employee throughout) a useful salary. Successful students are, at the end of training, then contracted to a minimum period of service, say 10 years.
As for having faith in the banks, I think you are dreaming in your suggestion that HSBC has researched the market more than wannabes! Banks just aren't like that, I'm afraid. CTC and OAT have access to HSBC funds because they have made their own business cases to the bank. OAT's students have a lower expectation of employment on graduation because that is the nature of the course, so it is not surprising that HSBC demands greater security than for CTC's cadets, of whom the majority have an airline place allocated (though not guaranteed) at the start of their training.
HSBC have withdrawn the individual prefessional studies loan for pilots precisely because they didn't research the market they were in, and lost a good deal of money as a result. The current situation saves them the bother of researching it; OAT and CTC do it for them. Incidentally, I wonder if CTC and OAT are risk- (and thus profit-) sharing partners with HSBC in this?
Anyway, the point of this thread is that wannabes have a choice, and are entitled to inform that choice. This thread - indeed, this entire forum - is intended to provide information to help with this and other choices that face wannabes.
Scroggs