I agree that your answer shouldn't have been unilaterally deleted by a moderator, especially when that moderator also answered the question. I don't think the deletion was done maliciously, but the moderator should have asked another member of the mod team to take a look to avoid the appearance of impropriety.
I don't see any reason why the community shouldn't be allowed to vote on whether your answer is valuable or not. Your answer doesn't do a great job of explaining how the bit about political ads is relevant to the question, but that can be fixed with editing.
The answer should be undeleted and the author given the opportunity to improve it based on feedback from the community.