The following fix worked for me. I don't see any outbound traffic on Fiddler when typing searches in the Start menu or when actually running the search. Granted, Microsoft needs to make this MUCH easier to do; the VAST majority of Windows users have no idea what group policies are.
1. Run gpedit.msc
2. Navigate to Computer Configuration\Administrative Templates\Windows Components\Search
3. Set the State to Enabled for "Do not allow web search", "Don't search the web or display web results in Search", and "Don't search the web or display web results in Search over metered connections"
Be aware that software can choose to not use a system configure proxy. It's a good tool to use, but absence of traffic in fiddler is not a definitive result, not least because it's tracking http traffic only. Wireshark is probably the next best option.
1. Run gpedit.msc
2. Navigate to Computer Configuration\Administrative Templates\Windows Components\Search
3. Set the State to Enabled for "Do not allow web search", "Don't search the web or display web results in Search", and "Don't search the web or display web results in Search over metered connections"
4. Reboot
Enjoy. :)