I prefer anal, although these days I don’t turn down PIV either. But my anatomy is different (intersex). I started out with a really tight vagina that made PIV uncomfortable. Its good now, but I still can’t cum while something is in my vagina. I have a lot of fluid to get out, and feeling stopped up like that causes problems.
So, PIV for a start, then anal for the finish.
if in the act i push a cheeky finger in her… she says NOT MY BUM… Im just learning to explore this p-spot thing but not quite there yet…
Anal
The only time your partner will tell you his Willy is small is when he wants put it in there 
My wife loves both PIV and anal. She said that her orgasms are more intense in anal and when she’s having multiple they continue to be strong as opposed to PIV where they lessen the more she has.
I personally prefer vaginal sex more than anal sex (and I’m in my mid 30s), but I do enjoy anal play a lot 
I agree with some earlier comments that it has more to do with preference than age. It’s possible older women might like it more than younger women if they just have had more time to have more sexual experiences, but I’m sure there are just as many older women who prefer vaginal sex as there are younger preferring anal 