Everything (save for artificial intervention) is getting cheaper, starting from commodities. This is true when measured with a constantly shrinking measuring stick in fiat. Now couple with technological progress and you will see why the price of un/low regulated products keeps dropping.

Modern TV sets are data harvesting computers with big screens and producers make a lot of money selling the data they harvested from you. Some make lore money from selling your data than from the hardware itself, they decrease their profit margins on the hardware to sell more TVs to harvest more data which is more valuable.

The Verge

Vizio’s profit on ads, subscriptions, and data is double the money it makes selling TVs

Vizio’s business model doesn’t end once you buy a 4K TV.