Darth Malgus told my Sith pureblood than the age of purity had ended.
After the flash point called the Red Reaver or something along the lines.
It's because Alextrasza, Nozdormu, Kalegcos and Ysera are mortal now.
I blame Thrall.
With the subject of the Red Reaper being what it is (Return of a pureblood sith lord from "way back"), I would guess that its directed to the sith lord in question. I'm guessing we learn more on Illum and in the FPs on there.
There's some major Empire story changes on Illum, based on what I understand from some of my guildies questing through there and clearing the FPs. I haven't quested much on Illum yet. Its next on my list of cool places to go, now that I'm 50.
You shall find out more when you quest on Illum. Needless to say, I was surprised at what happened.
"Laws should be made of iron, not of pudding."
“A good act does not wash out the bad, nor a bad act the good. Each should have its own reward.”
- King Stannis Baratheon