Stadia died because the product doesn't make sense. Stadia is essentially trying to replace a gaming PC. To offer this service you will have to charge users enough money to: 1. buy a gaming PC every 3-5 years 2. run it at ~250W for average play time (4-8 hrs a day) 3. pay for all of the bandwidth on your end And then you can offer the user a worse service than if they had spent that money on a PC themselves. Where's…
I think this is the important aspect. If you're only using it for a few hours a day, the hardware can be used for someone else while you're not playing.
So it runs into the same issue as autonomous taxis: the hardware is only useful in a narrow region and most users want to have their go at the same time.