Maybe try some of the solutions here -
https://www.reddit.com/r/samsung/comments/1..._from_gmail_on/

that is the reason why samsung customer piss off , spend premium price for flagship but yet getting such quality of screen , people willing to spend on flagship because they wish to use for a little long time , but if the light saber happen after 2 year of usage , no point if samsung promise to give up to 7 year of update. 
Actually s20 era stil less kena light saber problem , i believe macam start from s21 era , the light saber effect more user , because s21 used back the flat display with super thin bazel , plus the s21 use the snapdragon 888 which famous with OVERHEAT issues , the s22 8gen1 also having Overheat issues.

But it's sad to see even though s23/s24 already using TSMC design 8gen2 8gen3 , it stil cause the light saber  , might be samsung dont do well cooling system for their phone.