Could I humbly suggest you to do more reading on "mini led" vs "oled" instead as you're looking at the wrong technologies.

QLED TVs are still LCD TVs with LED backlight but with an added "quantum dot layer". But this is something common, which most LCD TVs come with...

So right now the industry is still ONLY divided between LCD and OLED.

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The thing you should look out for in LCD technology is the type of backlight, which currently mass market available is "MINI LED". This is way more advanced and more $$ than conventional LED backlighting or "full array local dimming" (FALD) tech you may see in some TVs like Sony or others...

Why is backlighting important? This almost essentially equates to picture quality...

The reason why the colours on OLED pop so much is due to the infinity contrast aka pitch black. The individual pixels are self illuminated and can turn off individually as opposed to LCD which needs a backlight to light up the pixels..

Mini LEDs mean the backlighting are composed by tiny mini LEDs which enables selective scenes to be lit up instead of the entire scene. This means darker scenes can remain dark.

For now, OLED is still king of picture quality, deeper blacks than mini LEDs, however, OLED has the relatively lower brightness compared to mini LEDs. This is crucial if your viewing environment is going to be bright. But in a dark/pitch dark environment, OLED is still king.