The whole point was to diversify their business model.
The tech behind Stadia is very impressive, I could play Cyberpunk 2077 on my TV/Mobile/iPAD/Mac with no lag in 4K.
Stadia integrated into YouTube could have been a Twitch competitor.
With Covid it could have been the perfect time to really launch the product when no one could buy a PS5/XBOX.
Google didn't invest in games, closed down their own game studio.
It's reminiscent of Windows Phone having no apps.