“Let my soul not enter into their council; Let not my glory be united with their assembly; Because in their anger they slew men, And in their self-will they lamed oxen” (Genesis 49:6).
Yes, he is. Other translations say “as they pleased” and that they were “self-willed” (i.e. following their own desires instead of God). In the preceding verses it says they keep “instruments of cruelty” in their place of residence and that their cruelty is what Jacob is denouncing. These were righteous Jacob’s dying words to his children, so they were intended to be the most important message he left to them – not to associate with those who practice cruelty toward humans or animals.