Instagram won't do anything about the post, they are as bad as Twitter forleaving tit like this up.
Sarah Ingham (of the Ingham Family) regularly posts account names so that their stans go after them.
Spotted an account on there with Yel's avatar and a username mentioning Tattle. They link to that ridiculous campaign to have Tattle shut down that was set up by some minor drama channel.
Jack, seriously for your own mental and physical health (blood pressure) just delete and block comments/accounts that disagree with you. Keep your little echo chamber nice and positive with mugs people posting about 'fur babies' (sorry, boak) and 'woof floofs' (double boak).
I've never had a dog so can't judge whether Content is matted or just generally scruffy looking. Apparently they shouldn't be clipped until 6 months (thanks, Google) so Content couldn't have her fur clipped before now.