I think the general public isn’t stupid in this instance, I think they’re just cheap. I have a friend who filled his house with Echo speakers and bragged that it was less expensive than a couple HomePods or Sonos speakers. When I pointed out that Alexa made shopping suggestions after a request he made, he kinda brushed it off, but a few months later he disconnected them all when he noticed private conversations around the house were influencing his Amazon recommendations. He’s fortunate enough to have learned from his mistake and been able to afford to fix it. A lot of folks see a 4k streaming device for $30, compare it to something like the Nvidia shield or the Apple TV, and think it’s a great deal. When they find themselves frustrated by advertising a couple days, weeks, or months later (or maybe desensitized to it like a frog in boiling water), it’s too late. They’ve already spent their money, and/or assume that this is just what all streaming devices are like, so why spend more for this experience?
Stupidity? Probably not, just cheapness and an ignorance of how low cost hardware stays low cost.
Kodi on a Raspberry Pi 4 is pretty good, and you can run moonlight from within Kodi. Of course, you have to find a reasonably priced Pi…
EDIT: Also, I use this setup in a spare room, but use an Apple TV in my living room for identical purposes. Though I use Infuse and the actual Steam remote play application.