The words 'religion', 'sure' and 'wrong' have no absolute meaning.
But in the specific context of 'religion' contributing to social and psychological identity, we can be 'sure' that historically religion has contributed to, fuelled, and at times instigated social strife. Insofar that such strife is 'wrong' then so is religion.
Those with an individual belief system which they might call 'religion' do not figure in the above analysis since they have contracted out of the 'social factor'.
NB. The word 'wrong' in the context of applying the word 'scientific' to a theory does
have a specific meaning defined by the 'falsifiability in principle' rule.