I'm not sure I understand - do you mean these suggestions are placed there by Twitter to deligitimize the original tweet [who, in that case, would have a valid complaint but is being maligned by association with the addition of "crank stuff"] ?
Or are you saying the original tweet is from a crank and the placement by twitter of additional "crank stuff" is proof of the crank label?
BTW when I view the tweet (also not logged in), I got no suggestions at all, so Twitter are presenting it in a different way to different visitors (i.e. you and me for sure). Perhaps you were part of an A-B test?
I don't know why it was showing this content. I don't believe there is any motivation like de-legitimisation, it's just their algo, possibly it thinks showing that content boosts engagement.