There is much more at stake than politics and votes. Regardless, much of here writings, whether some consider them too harsh or not, are quite true and and match the mindset of a good portion of Americans. I sense a fear by some that her writings may present the notion that Republicans may be "harsh". Too much concern about "appearance" IMHO.
If Coulter is held up as a test to weed out the fence sitters or alienates moderates then she's doing conservatives harm by sending votes to the other side.
If people are so moderate as to find themselves turned away from conservatism based solely on what Ann Coulter writes, then they weren't likely to vote for conservative candidates anyway. I would suggest that Ann's writings mirror the thoughts of many more people than several on this forum want to admit.
I agree with about 50% of what you wrote -- the other 50% isn't worth debating, except that I do believe it's all about politics and votes.
Coulter broke a fundamental rule of "media celebrity," which is never, ever come down hard on "normal people." The case can be made that the widows are no longer "normal people," since walking into the spotlight. However, they do come off as "normal" and that's what matters to viewers and readers.
Decades ago I read an interview with Prince Rainier of Monaco(and Grace Kelly!). It was largely bland, except the interviewer asked him about the concept of celebrity. He said something like, "It's like driving fast. Very exciting, but also dangerous."
Coulter would have done well to read that interview.