Why does Windows 11 cut internet speed?

Question

Windows

On Win 10, the speed was stable at 13-15MB. And then I decided to upgrade to Windows 11 and the download speed dropped sharply to 1.5 MB on average. Doesn't go higher. Where to dig?

Answer 1

On the command line or in powershell on behalf of the administrator, run the command:

netsh int tcp set global autotuninglevel=disabled

and reboot.
The speed immediately picked up.