Why doesn't the processor frequency "in idle" decrease to the base speed?

Question

Windows

Good day!
The situation is this. I have an 8th generation i7 laptop, turbo boost above 4GHz out of the box. Earlier I noticed that in idle time the processor frequency was below 1000 Hz in the region of 700-800 MHz.
And now it does not fall in idle time, it keeps more from 2.6 ~ 2.8 and above GHz.
And also, in order to avoid confusion earlier in the BIOS, I lowered the turbo boost to 3.3 Hz. I did this so that the laptop would not make noise once again. If you familiarize yourself with the specifics of the laptop, you will be aware.
For those who are interested, there is a video on YouTube on how to lower the turbo boost.
Screens under the hood.

Questions:
1. What will happen if idle frequencies are high?
2. And is it normal in general?

Answer 1

In your first picture it is written - CPU usage is 13%. Switch to the Details tab and see which processes are consuming CPU time. There is either some kind of indexing, or an antivirus, or a miner)