What is the motive behind the non-LDS Accusatory Tirade, "LDS are not Christians?"

Is it to inform and educate? No, because all Christians churches are "cults" and that cannot be denied, but they conveniently leave that out of the equation. So from the start it's an intellectually dishonest, specious argument.

It's a marketing initiative, period. If they put fear and doubt into the minds of consumers of religion, they may be able to cash in on a bigger share of the pie. It's priestcraft pure and simple.

It's as phony as "LDS worship a different Jesus." Of course it is the same Jesus. So it’s got nothing at all to do with anything remotely resembling a “different Jesus”, rather, it is just a different understanding.