re: 4k TVs are cheap. So where is all the 4k content?

BanaHater has stumbled onto the answer, albeit more than likely unwittingly. The porn industry has always been the leader in terms of adopting new standards of streaming, video equipment, cameras, etc. All the other content producers typically fall in place behind them due to their sheer strength in terms of disc sales, whom none could compare to.

The last time there was a big, market shift in tech is when the porn industry chose Blu Ray over HD DVD.

The problem with 4K and porn and the slowness to adopt, adapt and upgrade is that a leapfrog in content delivery is occurring.

Google, Amazon, Apple and smaller players like Netflix and Hulu are rendering disc sales and physical possession of a copy of the content you wish to consume irrelevant. The CDN's (Content Delivery Network) they've created online make discs less necessary for consumers as streaming threatens to make discs obsolete.

Porn content producers do not have the mainstream backing like the CDN players do, so for the first time, mainstream players like the heavyweights above are calling the shots re: content production standards. On the bleeding edge, nobody knows exactly what's next because there is no consensus or standard of what the next jump in resolution of picture quality will be.

Sorry for the ramble. Just finished my first cup of coffee.