The reason this could be worse than 2008 is that those methods will not work as well.
Part of the reason SVB failed so fast was because they held a lot of long term government debt, mortgages etc.
When they tried to sell it to provide liquidity for deposits they found there were not many buyers for it.
Since 2008, foreign purchases of long term debt have dropped from many of the main credit countries with no real replacement other than the federal reserve.
If the Fed moves from a buyer of last resort to the only buyer then that is game over. QE won't help because it will cause inflation. Inflation will move people, foreign countries and institutional investors away from long term debt.
Basically a hyperinflationary environment with systemic bank failures all caused by a sovereign debt crisis. Before long just funding the Govt will be impossible because the debt will no longer be seen as safe as it once was.
The difference is that the collapse won't be as immediate as 2008. It can be much more of a controlled demolition, until the methods they have used stop working.
It all just has to collapse at some point and reach an equilibrium again. It's only a matter of time...