All my previous phones can't seem to last a whole day before it requires charging. My current phone the Vivo X90 Pro's battery capacity is 4870mAh and it can't last up to 12 hours with moderate to heavy use, and I will need to charge it in the afternoon as the battery power drops to less than 50% with moderate to heavy use.

I was wondering, if looking at the battery spec what is the capacity that one would be looking at for the phone to last at least 12 hours with moderate to heavy use, say 7am to 7pm. Will a phone with 6000mAh+ battery capacity be able to last up to 12 hours with moderate to heavy use?

Ok, will check later. I have just checked the battery capacity on few phones on GSMArena but not on the endurance.

Xperia 1080P display, Vs 1440P from Vivo...sure lah. You try previous Xperia 1 V, 4k display without LTPO...screen stay 144hz all the time, even idle...it cant even last half day. Either battery low, or overheat warning popout asking you switch from 144 to 60

I watching 4k youtube, it always pop out after 40 - 60 minute. 4k video recording, 20-25 minute, warning will pop out.
1 day half..you must be using lower resolution and 60 fps.  4k resolution + 120hz refresh rate cannot tahan...