Soviet 746th Tank Regiment

[Legbreaker]

I agree. Chemical weapons are unlikely to deliver large amounts of equipment into the hands of the Soviets (or Nato for that matter).
Most modern AFVs include some measure of NBC protection. This alone will assist in keeping most vehicles out of enemy hands. NBC decontamination would also be a high priority for commanders - decontaminating a vehicle should take less time than repairing a knocked out AFV. Of course there are a number of situational factors to take into account such as the availability of the necessary decon equipment.

I can see chemical weapons being fairly effective against infantry, but not so much against armoured formations.