I read an article this AM saying Pell is an imperfect measure of low income kids, though it dealt with the top 200 schools, which brings in a lot of schools not really discussed on CC.
The gist was that some low income kids don’t apply for Pell (not the case at the elite, say, 50, probably), and that Pell actually includes too many middle income kids as you can get some Pell at incomes well over the $30K considered low income by the study. Also mentioned some income-eligible Pell kids don’t get it because of assets.
It was an article with a fairly clear agenda, so YMMV.