The FED is slowly, ever slowly, unloading the mess of a Balance Sheet it had accumulated as a result of the mess of 2008. FED Chair after FED chair took actions which will be debated for generations to come. Lots of PhD theses for economics types.
The balance sheet above shows the explosion of everything, especially buying Treasuries and Mortgage Backed Securities.
The two above show that much of this is of recent parentage. The MBS mess is truly a mess, and as the FED unloads what is truly worthless, that is the problem.
The above is the worthless junk. Note the slow unloading of late under the new FED Chair. If you think interest rates are bad now just hold on to your hats.
Here is a close up of the two elements just as it rose and then just as it seems to be coming down. Both are being unloaded. I suspect the Treasuries are due to timing factors and that the FED is no longer buying.
I suspect that long terms this must be watched carefully. One just has to see how much more is needed.