Apple is only interested in selling products with a high margin, like 50% or more. TVs don't have that.

If there will be a TV with Apple tech in it then this will be because the TV manufacturer has licensed a chip with iOS on it that runs the AppleTV flavor of iOS.

Or can you imagine people carrying home a 50" AppleTV TV from an Apple Store? If you cannot sell it in an Apple Store then Apple won't do it because Apple needs people to experience their devices in an Apple Store to allow them to fall in love it them.