As I've explained, in 2010, the budget deficit was 10% of GDP. I.e. the government was committed to borrowing 10% of GDP every year. It took the government until 2017/2018 to bring the deficit down to a figure which could easily be managed without significant annual borrowing (for example via quantitative easing) During that time, national debt increased significantly as you point out. Because every year there was a deficit between what the govt was spending and what it was making via revenue, it had to borrow to plug the difference.
Did you even look at the video? Or does that not meet your confirmation bias?
Head in the sand stylee.