And the answer is that they are heretical - as they are.
Of course they are blasphemous, etc.
And I will note that this statement does not set up a rating system of one heresy against another, nor does it exclude the possibility of other Christian groups with beliefs even more outre.
My point is -so what ? You are all heretics with unsound doctrines. We get along, more or less, why shouldn’t we get along with Mormons ?
I see you are responding to #270.
The 'reason' is found in #273.