Is it wrong to judge others? Yes and no. Stan Fowler writes about how the command to judge is often misunderstood:
When I look at Jesus’ words in their context and consider the fuller biblical witness, I conclude that whatever Jesus meant by “Do not judge,” He did not mean that it is always wrong to express a negative evaluation of other persons…We need look no further than Matthew 7 to see in Jesus’ own words that He surely did not forbid all expression of negative judgment about others, and this is confirmed by the wider biblical context.
What, then, did Jesus mean when he told us not to judge?
The statements that follow this prohibition actually make it quite clear that the Lord’s point is to warn us against judging hypocritically. He reminds us that we will be judged by the same standards that we apply to others, so we are wise to make sure that we can live with that before we express judgment (vs. 2)…The point is to deal with one’s own sin first before trying to deal with the sin of the other, but this does not amount to a prohibition against confronting the other. In fact, that is affirmed as the sequel to self-criticism (vs. 5).
Stan’s whole article is worth reading.