>But how does that make logical sense given that Gmail is free which means it costs money to Google and yet it gets to live forever but Stadia has paying customers and it's not good enough?
>[...]
>Unless I'm being more than naive and we the users are quite LITERALLY sold out to advertisers.
Yes.
Because when you can read every email and store it for data analysis focused on "targeted" ads, you can charge your customers (that's the advertisers, in case you thought it was gmail users) more when they invade your privacy.
Stadia is (or rather, was) chump change[0] at best, and it's a lot harder to spy on everything someone does online when they're just playing games. And pausing game play to show you ads...well, that would certainly never fly.
Remember, Alphabet exists to generate profit for their shareholders -- not to make cool stuff or make their product^W users happy.
If flooding every gmail user's inbox with Goatse[1] every six minutes would increase revenue (and/or stock price), a billion people would be intimately familiar with a stranger's rectum. And GOOG would laugh all the way to the bank.
[0] https://www.merriam-webster.com/dictionary/chump%20change
[1] https://en.wikipedia.org/wiki/Goatse.cx
Edit: Added the missing link, fixed formatting. Added link explaining what Goatse is, for those who are too young to have had the "pleasure" of experiencing it themselves.