I can be kind to all people, but that doesn't require that I have to ignore the quality of their decision making.
Learning to use agency (and wisdom) requires that we evaluate the quality of our thoughts and actions and others, and to do so without condemning either.
Additionally, unbridled kindness often is used to conveniently obscure much more often preached subjects like Cleanliness. We take the sacrament each week to be clean. I have yet to read anything about "no un-kind thing" not entering into to kingdom of heaven.
Kindness is a great attribute, but it is only a facet of another Christlike attribute: wisdom.