We might well ask, when thinking about this verse (and others), why didn’t matters come to an end in the first century? The fact is that both Revelation and Daniel could have been completely fulfilled (i.e., the kingdom established) in the first century, however, this did not occur because the Jewish nation attempted to deliberately corrupt the first century church.
In order to stop the rot the Jews were expelled and the temple destroyed, vindicating and (temporally) saving first century Christianity.