One thing to keep in mind is new technology or cutting edge products, allow for higher profit margins to the manufacturers.
Once all of the companies make a 1080p TV for 300.00, their profits are slim.
Of course there is RnD with new technology, however my point is the TV manufactures couldn’t care less if there is content or not, they just want people to buy their TVs.
If you were buying a TV right now for 2k but for 2,500 you could buy an 8k, would you not buy the 8k? (Even if there was no content, many people would spend more to “future proof.”)
I wouldn’t hold back buying a 4K TV today, as it will take time for 8k prices to drop, but it will not be “decades” before 8k is the norm.