How were the investment bankers significantly responsible for the 2008 financial crisis?

Investment bankers played a significant role in the 2008 financial crisis by promoting and selling complex financial products, particularly mortgage-backed securities (MBS) and collateralized debt obligations (CDOs). They often misrepresented the risk associated with these products, leading to widespread investment in subprime mortgages. Additionally, their practices of excessive leverage and short-term profit focus contributed to a lack of transparency and accountability in the financial system. When housing prices fell, the collapse of these securities triggered a global financial meltdown.