Why do we say "he asked after you" not "he asked about you"?

What are the origins of "ask after" and is it dying out as the way we currently speak?

Solution 1:

Oxford Advanced Learner's dictionary says that this is a phrasal verb which implies being interested in "how somebody is, what they are doing, etc.", i.e. it's not necessarily about health or well-being, but trying to sound in a general way more personal and more caring, a step closer to the people you mention.

Here is the link: https://www.oxfordlearnersdictionaries.com/definition/english/ask-after?q=ask+after

It seems to me that saying 'ask about' is slightly less personal that 'ask after'. Such differences must exist due to nuances in meanings.