I changed my mindchanged my mind about url shortening services, they indeed do more harm than good in SO ecosystem. I still think it doesn't make sense to call someone as a spammer just by using it, but I do believe it's bad for "link health" in long term.
So, I would like to do a suggestion in this answer: SO could just rewrite these links, maybe using an API from longurlplease.
(I don't know if SO team are really going to depend in a third party service like this, but since url shorteners are a problem from every site that supports user generated content with links, I still think this is a valid and useful concept)