While I agree with a lot of this article, it feels like the author somewhat misses the point of cloud gaming and makes a pretty big assumption about the average gamer.
Not all gamers, even the serious ones, have top end hardware all the time. It's a bit arrogant to even imply that. It's expensive and a hassle to even buy top end gaming hardware and while I recognize that's an indication of popularity, it's also heavily influenced by timing. Cloud gaming is very new while traditional hardware is established. No one, myself included, is prepared to skip this gen for cloud gaming but next gen? Maybe, that's a long time for people to accept it. Digital only games were "doomed" in the beginning too but things changed.
In theory, cloud gaming gives any gamer access to the best possible experience. That's it's main benefit. Not playing Assassin's Creed on your phone or similar. Being able to play Assassin's Creed Valhalla seemlessly at 4k with ultra quality graphics on a $50 Chromecast or the Nvidia Shield I already use as my entertainment hub.
The audience you can't identity is PC gamers who don't want to maintain gaming rigs anymore and console gamers who want better quality. The fact that we JUST had a hardware refresh obfuscates things a bit because they're the most powerful they'll ever be right now. But let's talk in 2-3 years and see how they handle modern 4k gaming.
I think cloud gaming is the future. In the end, it's better for everyone involved. Stadia Pro provides a great experience but Google will probably screw it up and the first party thing sucks. Still, the Xbox Game Pass model isn't bad and easily adopted. Stadia Pro BADLY needs to expand their free offering but I definitely see it as a viable model.