I can see the brightness argument, OLEDs are a little dim at times, but that aside they murder LCDs in every possible way. I say that as someone with a high end LCD PC display (1000nits, 512 zone FALD, 2ms response, GSync etc). LCDs are smeary, suffer from catastrophic haloing (or just an inability to render anything resembling black), and just aren't especially sharp or crisp looking. They're also big chunky things with noisy fans to cool the FALD. Oh and the actual pixel response time is way worse than the on the box ms timings, as their actual per pixel cool down decay time is comical.
If OLEDs can ever get to the 1000 nit mark, they'll be pretty much perfect. Perhaps micro LED will be a competitor, if it ever makes it to market.