Software he has been significantly involved with has caused problems for a lot of people in the past. The recent strife and disagreement surrounding systemd surely hasn't helped the situation.
If somebody has had bad experiences with multiple software systems developed by a particular developer/project/organization, it's totally understandable why they'd want to avoid that developer's/project's/organization's software in the future. Nor is it unreasonable to want to protect oneself in such a manner. Furthermore, this can be the case without holding any sort of hateful emotions toward the developer/project/organization in question.
Do you have a better name for such a flag that may not involve his name directly? It does seem like a very descriptive name for what it does, even if some people may incorrectly interpret it as being "hateful" or something like that.