I disagree with that point that: “so anything before last year is an LED tv and before that just lcd tvs”.
Well, LCD pannel as all will agree can either be backlit by a CCFL (cold cathode florescent lamp) or by one of the permutations of LED (edge lit or direct lit). Thus, what manufacturers refer to as LED TVs are actually LCD pannels with LED backlight. Which means all TVs (including LED TVs) use an LCD pannel.
Quote on “LED-backlit LCD”: While not an LED display, a television using this display is called an LED TV by some manufacturers and suppliers. In the UK, the Advertising Standards Authority has made it clear in correspondence that it does not object to the use of the term LED TV, but requires it to be explained in advertising.
Read here: https://en.m.wikipedia.org/wiki/LED-backlit_LCD