Earlier quoted context omitted.
Considering the lack of coordination of their ground forces and their absurd OPSEC, it might simply be communication issues. Fuel and maintenance issues are also a safe bet with Russia. The Russian Buks also seem to be having a bad time against the Bayraktars.
> The Russian Buks also seem to be having a bad time against the Bayraktars. Why? Small radar signature?
Buks are ideal for taking down a big jet aircraft flying at 10000+ ft.