Internet speed tests are high but downloads really slow a few KB)

[DVDR_Dog]

Just want to hop in here. In the US anyway wireless carriers have been offering "5G Home Internet". I run into all kinds of complaints over forums for these services. They run from trying to use their phone while still having their home connections in use. There are all kinds of limitations with max bandwidth caps. My advise, if you have any alternatives and you are visiting this forum, this type of service is not for you.
Even the most generous "unlimited" wireless services have data caps that slow you down to crawling speeds after the data cap in the contact.

 

[AFFASocial]

In your adapter and in your router just change the DNS to 1.0.0.1 and 1.1.1.1, and it will be blazing fast

 

[DVDR_Dog]

I was just looking over those two update Microsoft had you uninstall.
KB5028851 Deals with .NET security, it would seem is the difficulties you were encountering were related to this update, it would more or less be site specific rather than 'net wide.
KB5028185 Has a whole bunch of goodies packed into it, mostly silly or cosmetic with the exception of one item: "This update addresses an issue that affects File Explorer (explorer.exe). It stops working." That was buried deep inside the update description. That's a very serious problem if you encounter it. They don't explain what might be causing it. Hmmm.