If you have a gaming PC you don't have any use for Stadia.

If can't afford to shell out £1500 on a gaming PC, there is already a solution for you. It's called a games console. Plus they come with the benefit of having some great exclusive games.

So that's most people gone right there.
The remaining people whole can't buy a gaming PC, don't want a console also need to have a lightning fast Internet connection.
So how niche is this market Google are looking at?

Must not own/want a PC

Must not own/want a console

Must have a solid internet connection

Must not have data caps on that connection

Must not be far away from a data center to reduce input lag

Must not have an issue with "always online"

We're surely talking about billions gamers. Not necessarily in our solar system, but let's not be pernickety.    

The people that keep comparing this to Netflix just don’t get it.

Netflix, Spotify, Hulu, Apple Music etc are all non interactive mediums. Buffer times and lag don’t matter.

I see exactly one solution that would make Stadia (or OnLive (RIP)) as a streaming service: It will/would work if you stream the code/assets, neccesary for the moment, but being run locally. But this would mean you would have a standard consol with just a shittier e-shop.

That is rather silly,it is not like the fun you had with it will magically dissapear if google stops supporting the platform.

How is it so hard to comprehend that some people just do not care about a library of games that when having it they do not make use of anyway,it is personal preference like going out to see a movie instead of buying the phsysical copy and joking about people that show that behaviour comes off as being a bit shortsighted.

You're over estimating the lag issue. Most people play on TV's that might have an input lag of 50ms or even worse. Adding 20ms to that for playing on a cloud? Some people won't even notice, get yourself a 1ms monitor and you'll have a more responsive game than playing on your average tv locally.

I got 18ms when I was using a cloud based server in Paris, 460 miles away from where I live. Shadow, the service I was running only had 5 data servers in the world and this was the closest to me.

With the massive infrastructure Google has I imagine the ping will be even less than 18ms.

The average gamer (who doesn't go on sites like this) somehow doesn't even notice the difference between 30fps and 60fps.

But the average casual gamers will play on any device they already own, like phones and tablets, and if they want to play on TV too, they'll buy any cheap console, well marketed and with a game library large enough, Google should persuade them, but if it starts explaining Stadia's features, it could also expose its weak points, compared to existing competitors, in a way casuals too could easily grasp.

I think people still care very much about having access to their games whether it is physical or digital. The XB1's "always online" requirements that MS took forever to back down from, showed that people care very much about having access to the games they bought. This isn't a physical vs digital issue. It's a Denuvo/EGS level DRM issue. Steam may force you to use the launcher, but at least there's an offline mode, and at least Steam has been around for a very long time. Once EGS or Stadia goes down that's it. You no longer have access to those games. 

Going out to see a movie is $8 while a Blu Ray is $25. Movies are a couple hours long while games last 20 to 300 hours. So that analogy doesn't hold up at all. It is comparing apples and oranges. 

I only posted the comic for its points on why Stadia will fail.Sure it pokes fun at some things, but that's beside the point. Very few people fall into the category of having good internet, living alone, not already owning hardware, not caring about a small selection of games, and not caring about losing access to games they paid $60 for. 

Stadia will offer elasctic rendering, allowing more than one unit of the datacenter to be used for one game. Even if the feature is only limited to 2 units of the system to be used per one single game, 2 cpus/gpus working together are already more powerful than the next gen consoles. But off course, power is nothing without games.

Stadia/Xcloud will be a good option for PC games that are not willing to spend on upgrading hardware anymore and mobile gamers that would love to play some PC-quality games but don't want spend cash on a PC/Console either.

In order to attract more traditional gamers, Google would need to pump a lot of money in order to develop AAA exclusives on par with MS/Sony. They have money to do that, if some very solid AAA exlusives pop on stadia in the future, they would entice the traditional gamer to buy them and play at least on the free version of the stadia.