smart/strong guy well-respected on reddit
Why? Because the mobility to squat (rather: the ability to rise from the floor without using the arms) is directly correlated with mortality.
European Journal of Cardiovascular Prevention & Rehabilitation(no it's not squatting specific, but if you do not have the mobility to squat, you cannot do this).
As for your point about dietary recommendations and the like, I entirely agree, but that's not a thing I care about or want to fight for. Others certainly should, though. I much prefer to champion the cause of movement quality for general health and longevity. To this end, I believe everyone needs to squat regularly in some form, but it doesn't need to be heavy and it doesn't need to be a back squat. As long as the movement pattern is present.