Haven't faced many all-Russian groups in 40 man bgs in my time, but on smaller maps they are very beatable for the most part. Yes, you'll get placed in plenty of shit groups where the Russians co-ordination gives them a massive advantage, but I've had many experience where myself and 2-3 other skilled players somewhat half communicating were the difference, leading to some of the most fun i've had in random bgs over the years.
The average Russian just ins't that good at PvP from my experience. If you outplay them, their co-ordination won't save them. Nothing more satisfying than dismantling the hive mind knowing your team wasn't nearly as prepared and your comp not nearly as balanced from the start