Why, thank you for the swift replies, fellows! I'm new around here, so I greatly appreciate it!
I would not describe the person's phrasing as a threat either, just as disgusting and awfully mean-spirited. Being that none of my rights were violated as such, they are most certainly well within their rights to both have and express that opinion (this I don't think to be very controversial), I just don't know that given Twitter's guidelines that it is the appropriate platform to do so.
Another thing that motivated me to report this particular individual is that I keep seeing Twitter itself applying their so-called "safety procedures" and rules very inconsistently, something I personally think they really had ought to work on.
As for the legal issue, it was never really my intention to discuss this, though I can see how my phrasing might have given off that impression. Being that I live in Europe, FoS is a very important issue to me. Here we have all kinds of laws which prohibit certain types of quote unquote "hateful speech" (which occasionally extends to certain kinds of non-aggressive behavior), which I always found to be utterly ridiculous for a number reasons (see for instance the story of a scot who was arrested after having taught his dog to preform nazi salutes on command as a joke).