I changed my oil today and noticed on the oil filter box, it said, "New size, same performance". I new when they said new size, it wasn't going to be bigger. I took a side by side comparison pic. At least they're still made in the USA.
Motorcraft made that change a few months back. I suspect it is so they can fit it on more vehicles and reduce the number of different filters they have to stock. Then again, it could have been a cost cutting measure.
If you check all other comparable sized filters in the past, you'll find they're "all" the new "smaller" size. I noticed that back in about February or so of this year when changing the filter on my Ranger.
I would suspect this is just a cost savings measure on the part of the filter manufacturers.