My understanding is that due to Webb's location at L2, it can never point back at the Earth, because that would basically be pointing directly at the sun.
I read that as meaning "Pale blue dot" in the sense that Carl Sagan wasn't a professional astronomer or a NASA employee, he just said "Hey, wouldn't it be cool if you tried taking a photo of Earth from the Pioneer probe" and they did it.
Sagan was a professional astronomer in Cornell's astronomy department, but his rationale for making the pale-blue-dot image was less as a scientific endeavor and more as a way to tell us more about ourselves.
It also can't be pointed as the the optics need to be actively cooled, hence the giant sunshield and cooling pumps, so it'll never point towards earth/sun