Oh, I agree. $1,200 monitors are mostly better than $300 ones.
A more interesting comparison here IMHO is with panels using the same technology, sold around the same price (IPS or VA) and lacking Mini-LEDs backlighting.
Rtings seems to conclude that Mini-LEDs backlighting is far better than full panel back lighting.
Hell, I'm using one right now (KTC M27T20, paid 330 euros) and it's just amazingly good... even if not as good as OLED.
Also, right now, OLED also suffer from text fringing issues : https://www.flatpanelshd.com/news.php?subaction=showfull&id=...