US judge blocks Trump’s order to end birthright citizenship

I could be wrong, but I think this could be due to how the states' suit is worded? As in, I think it's worded as, "you can't do that in our state," and not, "you can't do that full stop."

From another site:

Attorneys general from 18 other states also sued over the order in federal court in Massachusetts.

Brown [AG filing the suit] noted his lawsuit is similar, but said he felt Washington should lead a separate case because of “specific and unique harms that are brought here.” He also said that “we have a very good set of judges in our bench here in Washington, so I feel like this is the right place.”

(My emphasis.)

So, a good first step, and while this should be struck down in its entirety, my reading is that this was a lawsuit with limited scope, and the injunction matches the limited scope.