1st: not serious.
2nd: DC has had bumper stickers and license plate holders with “Taxation Without Representation” and black leaders making speeches about statehood for DC. Would be 2 Dem US senators, a Dem governor, Electoral College votes and the rest forever.
If Staten Island shouldn’t secede or become a state of the union then DC should shut up, too.
Fair enough.
Staten Island merely wants to secede from New York City, though, not the state. AFAIC, Article IV Section 3 of the US Constitution doesn’t apply here.