I bet MILF started to be used in porn when all the content providers had problems selling their housewife content as they weren't teens and not mature either
No matter what - Housewives and milf has allways been my best selling stuff and they are fucking hot (and they has the experience too opposite to teens who look good but know nothing) MILF MILF MILF. We want MILF.
Enough, I will now have dinner with my MILF wife.