Just my experience.
But, I have a masters 1st class aeronautical engineering.
Post flight training ended up flying 3 years in light twins (freelance, where I worked part time making use of my university degree to fund poor salary), now 3 years regional turbo props (which I absolutely love)
Have applied many times for easy, aer lingus, jet 2. No interview.
So in my opinion the degree has not helped my flying career, however some might say I have been very fortunate in getting where I have. The degree might help with the sort of jobs that value life experience. But if a jet is where you want to end up... Luck and the right integrated school, and LOTS of money open doors.
Due to the financial implications of university these days, make your own decisions. I found my wife my friends, lifestyle through sport at university. So very glad I went. Plus I funded most of my training with my career post uni. However didn't have to pay fees.
At 15yr old, I suggest you make the most of school. Work, get good grades, get involved in sport, or extra curricular option that enhances a CV. Open doors to your future. Don't make decisions now that limit options.