Reading the quote, it does not sound ambiguous to me, actually, more like a threat. This is political art, not unlike the trash that the Whitney in NYC displayed for much of the '80s (eventually they changed curators). This city commisioned art that (essentially) advocates the overthrow of themselves. Perfect.
From an artistic standpoint, there is an argument to be made for the ambiguity. Whether or not they MEANT it as a threat, I can't say, but judging from the "and will be again," in the second quote -- it certainly sounds somewhat threatening. That, however, makes the ambiguity argument no less logical, particularly from an artistic standpoint.
I just hate any and all divisive identity politics -- and this certainly falls in that category.