DC has had home rule for over 50 years. If this is a 30-year low in violent crime, it's all the more proof that radical change needs to happen soon, not something to be proud of.
Unless other US cities were countries, in which case there push it off that list.
You seem to be very invested in the idea that cities like Baltimore, St. Louis, or New Orleans have it worse. You're right. What relevance does it have?
How is this different from "when did you stop beating your wife?"
You've pasted the Wikipedia link three times in this thread. What is your motivation for doing that? Do you support the takeover in DC?
The reason he gets away with it is a legislature and supreme court (note: only the supreme court, not the rest of them) who have decided to bow down.
Do not pretend this is lawful.