The DAC is, but the amplifier that's after it certainly isn't.
And there's no line-out, so you're effectively dual-amping any signal if you use an amplifier on the built-in 3.5mm jack.
In any case, I think they should have kept the onboard jack, and people who really care would continue to use external DAC/Amp stacks.
There are valid product reasons for moving away from the 3.5mm jack though, like adding a power line that allows you to make active noise-canceling headphones that don't require their own battery, or outputting to more than two (stereo) speakers over a single cable.