The Mordechai infers from this Gemara that under normal circumstances when the rabbi of an area is not similarly preoccupied, he has an obligation and a mitzvah to erect an eruv for his community.
Following this reasoning the Rosh in a famous teshuvah (21:8) sharply criticizes the leadership of a city whose policy was not to erect an eruv: “ I have already written to you concerning the concept of an eruv, that it is customary in all areas where Jews [reside] to allow carrying in those streets that are open on either end to the [streets where the] gentiles [reside] with [the rectification of] a tzuras hapesach. You forbade such [an eruv] for the congregation of Freres, and you wrote me your proofs, and I informed you that they amount to nothing. I warned you that you must recant and notify the congregation that they should rectify their streets [with an eruv] as their gedolim have accustomed them to. Now I have been told that you still uphold your position, and are thus causing the multitudes to desecrate the Shabbos. I therefore compel you, upon receipt of this letter before witnesses, to rectify the streets that open into the reshus harabbim of the [streets where the] gentiles [reside], with a tzuras hapesach, within a span of a few weeks upon seeing this letter. If you do not rectify the streets as I have written, I will excommunicate you. If you had been in the times of the Sanhedrin they would have executed you, as your aim is to uproot the Talmud edited by Rav Ashi, and to argue with all the gedolim until our times, those who are no longer with us z”l, and those who are still alive” (see also Tashbetz, 2:37).