First of all, thanks for proving you've not bothered reading any of the information I linked, because it clearly states otherwise:
So King Henry VII passed some landmark legislation. He proclaimed that begging in the streets be legal for people with disabilities. So into the streets, with their “cap in hand”, went King Henry’s disabled veterans, to beg for money”. So with cap in hand referred to beggars, or people of no value in society.
The term is also used in horseracing and wagering. It measures the superiority of one contestant over another. This is the belief that one participant is stronger or better than another. The word “handicap” is rating one thing better or worse than another.
It appears that “handicapped” seems to have begun to describe a wide range of disadvantages, including social, economic and even moral standards. The website by Arika Okrent (2015) reports: “Handicap began to be applied to physical and mental differences in the early 1900s, when the new fields of sociology and social work started looking at people in terms of their place in society as a whole”. The term was used to describe people viewed as physically or mentally flawed.
Second of all, disabled people reclaiming a word for themselves, no matter how friendly you are with them, still doesn't give you the right to use it to describe the rest of us (or at all except for if your friends specifically asked you to, and I'd honestly consider whether they actually want to be called that, or that they know that you would react as badly as you are here, so don't bother to correct you because they have better things to spend their energy on than educating a "friend" who would use them as debate tools to prove how not ableist you are. Hint: doing that is ableist), just like you don't go around using the N word or the F and T slurs, all of which have been reclaimed by their own community but are still derogatory when used by outsiders.
So like I told that other person:
you can choose to be respectful and make the tiniest adjustment to your vocabulary, or you can choose to continue to use a harmful term despite now knowing full well that it is harmful, proving to me and others just how little of a shit you give about disabled people.
I've done my part, the choice is yours, and you're clearly choosing to prioritise your own ego over respecting disabled people on the most basic level.
Which I guess only leaves me feeling sorry for your "friends" (or should I say tokens?)