I will just give my 2 cents on this. They may have reduced the drop rate, but I read somewhere that they increased the containers that would have drops. I was really bored and tired of grinding my Vet rank (btw.. how do you get to VR12 less than 48 hours after launch?).
Anyway, all I did today for about 3 hours was grind containers in inns/taverns/banks/houses in the VR9 and VR10 zones.
I found 3 Ancient Elf, and 1 Daedric. On top of that, about 50 Daedric hearts ( I think I had 3 sitting in the bank prior to today).
Now it was boring as hell, but after god knows how many hours and not a single motif since i left the starter zone, and I get 4 rares in a day.
Not sure if this proves anything other than if you're willing to grind containers, you'll get the motif's.
Just to be safe, I bought a lottery ticket in case today just happens to be my lucky day.
And just to tell the end of my story: it's a blessing that tey have lowered the drop rates, cause i never found so many motifs since the "nerf". Really, containers now drops stuff often, and got my primal today. So since the patch, without farming for styles, i looted 5 motifs (1 rare).
Thanks.