Apple Games is still going and Apple don't look like canning the Apple TV. Success comes in many different forms.I believe, that gaming on an Apple TV failed to take off in any appreciable way. I don't think its due to processor horsepower (or lack there of) but rather misjudging the market.
IMO the main barrier to entry into the console market is that Microsoft and Sony (Nintendo's kinda different) shovel billions into marketing and buying up game devs. They make biiig losses (billions) in order to penetrate the market and then hope to make it all back on subscriptions.
To me it's a mug's game that can only have so many players. I welcome Apple's approach of selling an 'Apple TV' rather than a console. If they can turn enough of a profit to make it worth their while without blowing the kinda money that M$ and Sony do on market penetration then I think they could go alright!
And yes... gaming is a side feature. IMO that's okay.