In absolute numbers there are more free games on PC (see itch.io) yes but that kind of doesn't matter. If your game choices are purely driven by cost then a second hand laptop with f2p games is going to be the cheapest approach. If you exclusively want to play f2p games, then a cheap PC or a cheap console doesn't really matter. Buy if you're going to be buying a handful of new releases a year, the difference is more like €10 per game rather than €50

> since you pay lower platform fees

The platform fees (not required by the way) are roughly the cost of one game per year, if not cheaper. Gamepass being a very different discussion (and is available on PC too)

> This is in addition to the opportunity costs you incur of not buying a PC or having a lower powered PC as a PC can be used for other things (ie, office work, taxes, other productivity tasks).

I don't know about you but I don't want my work PC to be where I relax in the evenings, and many people don't want their employers software or information on their personal devices. I also live in a country where I don't have to fill in my own taxes, and almost all of my personal computing needs are met by my phone.