Assuming a given gamer owns any PC with a moderately decent and current GPU, I really don't see why they wouldn't have a Steam account even if they preferred to play on console.
As someone who's had a Steam account since early 2008 and a library of 110 titles, I still generally prefer to play on console for shorter sessions, but the library of games I've built up on my Steam account will pretty much go with me everywhere with whatever PC I choose to build in the future.
Media, contrary to what a lot of people think is a lot less transferable and unless you don't plan on moving ever they won't always go everywhere with you. I have close to 30 years worth of games stored in various places which are pretty useless if I don't have immediate access or I need to pick up an old console to play those old games if mine is lost or broken.
Personally, the thought of "displaying" the hundreds of games I've accumulated over the years (I don't sell or trade in games) along with all the consoles to play them on has about zero appeal.
The only bad thing about Steam seasonal sales (summer and winter) is you will build up a back catalog of games you will have no hope of being able to finish by the next sale. Mid week sales are also great.
Eventually, services like Steam will be the future of the majority of all gaming.







