Pardon the glib reply, but if this is what Facebook considers "innovation" then I'm with the author of TFA. How does switching to a more obfuscated metric result in a better product or improved user experience?
Daily active people is the de facto north star metric for a lot of companies, and to move forwards and adjust their definition is interesting.
"Obfuscated" is a judgment we're making. I'm assuming internally it's very well-defined. Perhaps they need to better define it outwardly.
I am giving them the benefit of the doubt and if they are indeed doing it as obfuscation, I agree it's not good.