I was (am) one who from the start said 3D was a gimmick not feature. 4K is here to stay because it is a very different situation. Cost isn't a factor just as with HD TV's it was not a factor. Give it some time and the price comes down as it always does. You don't need anything extra like 3D glasses etc.. so even if what you are watching is not 4K no harm, no foul. It will take almost forever for broadcasts to be in 4K however, getting 1080P isn't even feasible now. So like 3D you will need a 4K player or if you have the bandwidth online programming. And for online programming good luck as internet rates are on the rise as are caps and slow downs and it's going to get worse. (Unless congress deems it a utility - then who knows)
Bottom line - Give it a little time and all sets will be 4K. But because of limitations I don't see everyday programming to be 4K anytime soon, certainly not undiluted.