Tesla1856,  You're right, the change win10 -> win11 went [surprisingly] easily, with the exception of the chipset drivers I mentioned initially for the ethernet. What actually took time was configuring 3rd party apps to make the start menu & taskbar work for me.  But other than that, win11 has been solid on my xps 13 9300 and xps 17 9720 laptops. What was irritating a bit was both windows update and dell support assist saying i was up to date, with no missing drivers.  But obviously I lost the chipset drivers, or links to them, during the xps 13 migration.  Oh, well...
When I finally installed win 11 on my xps 13 9300 laptop, the Realtek usb ethernet adapter disappeared.  The Killer wi-fi took over, but ethernet became non-functional.  Device manager didn't show the Realtek ethernet adapter, just the wifi adapter.  I tried resetting the network adapters without result. I uninstalled and reinstalled the Realtek drivers, even though windows update said everything was up to date. It was like the ethernet adapter had disappeared from my system.  It was not intermittent; it was completely gone. The solution was going to the Dell driver page, letting it identify my machine, and downloading the Intel chipset software, and installing that.  After reboot, suddenly device manager showed the Realtek ethernet adapter, and ethernet worked again on my machine (as it had for 2+ yrs under win 10). I post this in case anyone else had this happen.  It might be something to try...
XPS 9300 lost ethernet after windows 11 installation