I was playing in the 1.17 version but because I use BadLion cleint I have fullbright on. I started to notis that areas that should have good light levels during the day were spawning mobs. When turning fullbright of it was all dark. Also even when i spammed torches down it still didn't do much so now I no long have access to my house because it is filled with mobs.

Edit: I would also like to add in the area of dirt i had spammed torches so I removed them for the picture but before the torches mobs would spawn there during the day.