To say that the Geulah will be delayed...

To say that the Geulah will be delayed until the entire Jewish people repents is contradictory to many pesukim . . .

Considering how dismally our Sages describe ikvesa d’Meshichah (the time immediately prior to Moshiach’s coming) – how can it be expected for such a generation to do teshuvah completely?

Apparently, it is not the unobservant who are delaying the Geulah. . .

The Rambam’s ruling in Hilchos Teshuvah 7:5 that the Jewish people will be redeemed only by repentance, is a reference to people like us, [i.e., observant Jews] and believers; it’s not that we must wait until the entire Jewish people repent.

(Minchas Elozor [Munkatch])

After the Geulah

After the Geulah, when Hashem reveals His glory to all humanity, every Jew will repent as never before.

(Netzach Yisrael ch. 46 by the Maharal of Prague)

Those who remain when the redeemer arrives

Those who remain when the redeemer arrives . . . although they will be to blame that they did not go out of golus due to their unworthy deeds, nevertheless, Hashem will not consider their deeds forever, “for He desires kindness” . . . His kindness will overcome the sins when the time of the Geulah arrives.

(Radak on Tehillim 130)