It (SY BITS) is not, but it is quite capable of emulating it anyway. The basic waveforms are there (including PWM and noise) as well as sample and bit reduction to take the fidelity down a notch. Together with the ADSR and LFOs many of the old-school 80’s C64 tricks can be made, some of which I tried to use in the video. Much of my musical education came from using C64, Amiga and trackers so I wanted to see how close I could get.
One of those tricks was to rapidly switch sound or settings on every PAL/raster tick (50Hz), for example the toms which are made by one tick (20ms) of pitch drop, followed by a tick of noise burst, then followed by the rest of the pitch drop. That one was made using a combo of two LFOs, one for the pitch and one one-shot square that rapidly switched the SY BITS noise/tone balance from one extreme to the other.
Then, the SID has a single analog multimode filter, and that can be emulated by routing things to the analog FX block of the Syntakt and parameter locking it. However, in the ST each of the 8 digital channels also have two filters so it could in theory emulate a stack of C64s 
What is not there is things like the SID’s ring modulation, but on the other hand the DVCO can be used for such things. I might do some more experiments in the future, trying to emulate more advanced tracks including that, we’ll see!