Weren't Windows 7 and 8 already having "web search" enabled for the start menu ? I'm sure it was there, but not if that was default behavior or if it needed to be enabled.

Not a Windows 10 introduction, although that one tends to find any excuse it can to call home.

Maybe Windows 8? Because definitely not 7. I think it offered you to "search the internet" (aka bing), but it didn't do that by itself, you had to click that option.

Microsoft doesn't yield enough sales or profit from Bing for such a thing to matter at all, versus the profit given up from the free upgrade on their single most profitable product. Bing is a financial joke compared to Windows and always will be.

The free upgrade was to get people off of 7 and 8. Windows 7 was an aging product that people were reluctant to give up, and Windows 8 was a disaster that was accelerating the erosion of Windows and doing damage to a brand worth tens of billions of dollars. Windows 8 was acting as a product generation blockade, most 7 users didn't want to touch it, and people who bought it had a poor experience. Bing had nothing to do with the free upgrade at all.

The upgrade changed your search provider to Bing unless you were very careful, I believe in more than one place. It also tries hard to default you to Edge which would take you to Bing. And I believe it added lots of new agreements on tracking. There is now a Cortana/Bing voice search service that can't really be fully turned off that came with it or one of thelater upgrades I think.