Yes and no.
You typically end up with "Jewish" neighborhoods because: (1) you walk to shul --- ergo, you live by it; (2) shops that cater to your needs (e.g., kosher restaurants, butcher) logically locate close by; and (3) eruv points (related to sabbath activities) are expensive and hard to keep up, so you keep them in close proximity.
Relative to Orthodox perhaps, which is only 15%-20% of the Jewish population. And even they have contact with the "outside" world.