that's not a stupid question.
4K won't be catching on fire anytime soon, although it has caught on more than other recent TV technology. You look at how hard and how LONG it took to get ppl to convert to HDTV. Like almost a decade, they basically had to force ppl to do so. They had to sell TV's for super cheap Black Friday deals, told ppl their older TV's wold no longer work....people with less money or ppl who don't care tht much about TVs finally were able & forced to catchup.....but they wn't be changing again so soon. There's people with HDTV who are still content watch non-HD broadcasts.
Alot of people went from 20 year old TV's to a new HDTV...you think they're gonna go rebuy all new TV's again after 3-5 years? Nah. Not just to get 4K.