Will all body react same regarding thinning of hairs (not removal)?

I’ve had 8 IPL treatments on my back and the hairs are much thinner, they get thinner with every treatment. But I wonder, if the hairs on my back beomes that thinn, will the hairs on my other body parts react the same way? Will they too get thinner and thinner if I undergoe enough treatments or is it different depending on the body part? I’ve had only two treatments on my other body parts (the legs only one treatment).
I am not talking about removal (because I haven’t seen so much of that), but I mean thinning of the hairs.
Has anybody had experience with this?

from reading past experiences, it varies by body part.

So considering the fact that the male back is said to be the hardest area to treat, I could expect at least the same degree of thinning of hairs on my other body parts - or is it not so?