Thunderhorn Horde = Dead?

Been back on my OG Shaman for awhile now and I've noticed that Horde pop is horribly low. Low to the point that I wonder if there's more than 1-2 active progression guilds on Horde side with close to no real casual guilds out there? I run the Census+ Mod and I track only 350-500 active Horde on at any time.
Probably pretty accurate, according to wow-progress theres only about 1800 max lvl horde toons. Might be accounts with a max level toon on thunderhorn, not sure.