That’s pretty cool. If I go into the settings on my television, it reports its “Android TV OS version” and has a Play Store facility that I can navigate to (though I find that it’s often easier to install apps via “push” from Google Play Store on a phone or in a browser to the TV, if the app shows that it’s compatible with and can be installed on the TV). I don’t understand all the marketing/labeling nuance, which I think can get confusing, but my device definitely says “Google TV” on its home screen and shows a Google TV splash screen when rebooting. It’s not the deprecated “Google TV” platform that was apparently retired a number of years ago, but using the same label for different things certainly isn’t helpful. (Thanks, Google.)
If your recent Google TV purchase was of recent manufacture, then I would’ve expected it to essentially be an Android device, though that doesn’t mean it’s possible to install every Android app on it, and I imagine it’s like what was suggested in a different topic. I haven’t ever tried side-loading anything on the TV. 