The recession and why it happened from an amateur's point of view

I'm studying Macroeconomics and Microeconomics so I can say that I'm an amateur economist. I want to talk about why the recession happened from an amateur economist's point of view. It's going to be superficial and shallow so don't take it too seriously. Here we Go!

First, one of the reason for the the recession was how America spent money. Americans just bought and bought. The MPC was greater than 1 meaning that their consuming power was greater than that of their GDP. This made people have debts or make people use their savings to the extreme that they was their 401K. They also used their credit cards too much. Instead of paying fully for whatever they buy, lots of Americans paid the minimum price that they need to pay the credit card company an kept postponed their payment. When the deadline for the payment came, they couldn't pay and the banks couldn't get the money so they could pay off their debts to other companies and everything just crashed.

Second, the mortgage system is wrong. The mortgage system in America is that people borrow a huge sum from the bank and pay it back bit by bit and for 10 or more years. It might be convenient for the people since they can get their dream house even if they don't have the money. But, when the economy crashed and the bank kept trying to take back cash quickly and the people couldn't pay their mortgage, the mortgage crisis happened and Fannymay died.

Third, the way America kept minting money is another problem. America is in a huge debt and can't pay off their debts. In a condition like this, America would have gone through IMF but since the global standard for money is American dollars, America just kept printing and printing money to pay off the debts. This made the confidence in American dollars drop significantly. For example, China which has over half of the American bonds decided to not buy American bonds anymore because they thought that value of American bonds keeps dropping and dropping because there are American dollars getting printed as we speak and inflation is happening.

This is just the causes for why the recession happened from an amateur's point of view but I think that this is relevant to why the recession happened.