Frankly, I'm amazed at how much people could get worked up over a Twitter account for a 90's video game mascot. Hopefully there is a modicum of self awareness in some of the more serious comments.
I'm pretty amazed that a twitter account for a 90's video game mascot is tweeting punch-down ironic "check your privilege" jokes actually. I would normally associate that kind of humor with the chan and gamergate crowd, and not from a children's cartoon character, or rather, the employee running his twitter account.
Whether you think it's mocking trans people or not, the target audience for the joke is clearly the "anti-PC" crowd.
And as somebody who thinks of "political correctness" as synonymous with being respectful to underrepresented people, yeah, I think this was out of line.
I get that the point of the account is that the thought of a self-aware, meme spouting Sonic is funny. But there are ways of doing that without bringing a cartoon hedgehog into gender and identity politics. After all, it's done well enough so far.