I agree and disagree.
Apple TV is in its own market in competition with Roku and others.
I don't see it marketed (ever) as an accessory. Thats just bad business, never suggest a stand alone product as accessory. If you do you just cut out everyone that doesn't own the device it's an accessory too via your own marketing.
For the life of me I can't find the article but I was reading recently with the current generation (younger) are the people upgrading into the Apple ecosystem. Generally kids that were given iPhones and now old enough to purchase a Mac. Prior it was the other way around, likely due to how much longer their PC's have been around. So it's not out of the question for someone to invest into a company by starting off small.
Regardless, which do you feel is more of a way Apple should approach this (given only the options we've talked about).
A. AirPlay update that makes ONLY iOS device users run out and get an Apple TV.
B. Better Apple TV services to compete with the competition and then maybe getting some of those people go further into the Apple Eco system.