If Binance does it, the whole purpose of cryptos will be defeated. Crypto is supposed to provide us with an unrestricted access to our wealth. If Binance blocks access of a particular country, it will earn them a bad reputation.
I am sure Russian common population do not want war so they should not be the sufferers. Also CZ is a Chinese person by origin and China is one of the biggest supporters of Russia. That might be another reason for not taking any action.