While reviewing suggested edits, if the editor has removed a relevant tag it seems as though the best reason for rejection would be:
clearly conflicts with the author's intent
This edit deviates from the original intent of the post. Even edits that must make drastic changes should strive to preserve the goals of the post's owner.
However, many reviewers appear to be rejecting the edits using irrelevant tags as their reason for rejection:
This edit introduces tags that do not help to define the topic of the question. Tags should help to describe what the question is about, not just what it contains.
At first glance, the latter seems like it might be more pertinent to the situation at hand because it singles out the fact that the rejection is because of a tagging issue, but it never says anything about the removal of relevant tags in its description.
Normally I'd go with my instincts and stick with the former while reviewing edits, but since I'm seeing several cases where reviewers (with much higher rep than me) are choosing the latter as their reason for rejection, I'm wondering which choice is best for the community as a whole. If the answer is irrelevant tags, would it maybe be better to re-word the description to something different? Example:
This edit introduces changes to tags that either do not help or cause harm to the definition of the question's topic. Tags should help to describe what the question is about, not just what it contains.