The licensing authorities had to decide what is the minimum acceptable standard of training, and they did so - the standards are specified in documents.
The same as a car driver's licence - if you meet the minimum acceptable level, you get a ticket to learn. But you aren't ready to drive professionally, or a Formula One car or a semi-trailer.
In the military, the minimum acceptable level is way above the civil level, and is shown by the fact that a trainee scrubbed off a military course 75% of the way through is immediately eligible for a commercial licence after passing an exam. The military wants a better pilot, and they get it. Only about 10% of those who apply for a pilot course will graduate - there is a lot of weeding done via selection boards etc along the way.
But ANY civvy, even a tragic ********, given enough money, can get a licence. It just takes lots more time and money.
Making the course longer and harder might just mean you get rich dickheads instead of the not-so-well-off potentially excellent pilots.