It's about making more steam users. Windows is great, they can use steam. They're going after people who can't afford a pc. If people get a deck or steamos who already do own one, that's just gravy
The weird thing with this is i became a pc gamer precisely because it was the cheapest platform.
Most homes had/have a desktop pc. The hardware was mostly irrelevant because Low graphics settings where default and actually looked more readable then the dlss blurs of today.
Agree, depending on what you prefer it can be the cheapest or most expensive option. I remember playing left 4 dead windowed at 480p when it first came out