tmynx I think something to realize too is that MILF doesn't always mean old (at least to me). Sometimes it's more of a look than an age. I've seen some pornstars that are in their mid to late 20s that have a MILF look, so I think it's more that in some ways. I personally really like women who have an exotic/piercing look to them.
True about 'milfs' as the acronym has been watered down over the years.
In any case I still remember the discussions NA's representative Scott participated in years ago on Reddit that unironically is almost a copy of the same discussion we have in this thread. Anyway he said he back then he was unsure if the people asking for younger models weren't just a loud mouthed minority. He also stated he wondered if they really knew what the NA brand was all about - which was milfs/matures at that time.
Obviously they have changed tune since back then as milfs/matures is on the back-burner these days but why? It could be a lack of demand issue of course.
Personally though I believe the decline in milfs/matures in mainstream porn has nothing to do with a lack of demand. No I believe as stated earlier what a 'claimed' representative in the industry stated - high quality milfs/matures simply get locked into exclusive contracts or they are too expensive because they found find better paying pastures that didn't exist when sites like NA came to prominents - Onlyfans, ManyVids, livestream, etc. That simply results in a market were milfs/matures are getting harder and harder to hire which VirtualTaboo stated some years ago.
I fully admit I could be wrong but given milfs/matures dominate search results and watch list free porn sites release yearly I just find it rather hard to believe VR porn is somehow different in demand.