This is exactly it. The word has no meaning anymore beyond "those more socialist-y socialists".
I only really ever see it used in any remotely meaningful way that isn't attempting to be a though terminating insult when used towards people that have studied theory or those baby leftists that hang out online with us theory enjoyers.
Oh, and needless to really say but anarchists, by definition, can't be tankies.
I love the people who are very insistent that it's a well-defined political science term and not just an epithet that arose out of a single political disagreement ("during hungary") that they've adopted to mean any time someone opposes the united states.