There is no single LCD technology, VA, IPS and TN are very different in all of the criteria and there are tons of technical enhancements like local dimming.
And of course you can change OLED brightness.
I personally prefer VA over standard IPS because I cannot live with the bad blacks. Samsung got TV market leader because of their superior VA technology.
And I still hope that OLED will become affordable one day, they should be cheaper to produce than LCD already, the higher price is just marketing.







