Most people surely buy/bought their license with a new PC from an OEM; OEM's apparently always paid much less, e.g. 50$ (in 2009) https://arstechnica.com/information-technology/2009/09/micro... - and less if it was a cheap/low-end device: https://www.digitaltrends.com/computing/microsoft-reducing-w...

I'm guessing they're not going to drop those fees, so whatever ad or product-placement revenue comes in is probably on top of that?

Eh, it's the same. The price floor is just different.