Since when do LCDs have better viewing angles? That goes against everything I know from the tv industry. Color shifts when moving off angle? Also an lcd problem.
Brightness on the other hand is an issue for OLED.
LCDs have had better viewing angles since day one. I’m not sure what you know about the technology.
When viewing at angles, OLED loses due to large shifts in color vs. LTPS LCD. However, it wins as it maintains brightness better at angles. Most professional users are looking for color accuracy more than brightness.
Take a look at the measurements for iPhone 7 vs. iPhone X on DisplayMate.