To Understand a little of the Yerida of the Doros:

 FROM SOTAH 49b

"The mishna taught that from the time when Rabban Yoḥanan ben Zakkai died, wisdom ceased. The Sages taught: From the time when Rabbi Eliezer died, it was as if the Torah scroll had been interred, as he had memorized many secrets of the Torah. 

"From the time when Rabbi Yehoshua died, council and deliberate thought ceased, as he had the sharpest mind in Israel. From the time when Rabbi Akiva died, the powerful arm of Torah, meaning the exposition of all the details of Torah scripture, ceased, and the fountains of wisdom were sealed. 

"From the time when Rabbi Elazar ben Azarya died, the crowns of wisdom ceased, as “the crown of the wise is their riches” (Proverbs 14:24), and he was both a great Torah scholar and a very wealthy man. From the time when Rabbi Ḥanina ben Dosa died, the men of wondrous deeds ceased. 

"From the time when Abba Yosei ben Katonta died, the pious men ceased. And why was he called Abba Yosei ben Katonta? Because he was among the diminished [miktanei] of the pious people, i.e., he lived in an era when the pious had become few. 

"From the time when ben Azzai died, the diligent ceased; from the time when ben Zoma died, the exegetists ceased. From the time when Rabban Shimon ben Gamliel died, locusts ascended upon the land and troubles proliferated. From the time when Rabbi Yehuda HaNasi died, the troubles multiplied. 

"The final line of the mishna states that from the time when Rabbi Yehuda HaNasi died, humility and fear of sin ceased. Rav Yosef said to the tanna who reviewed the mishna: Do not teach that humility ceased, for there is still one who is humble, namely me. Rav Naḥman similarly said to the tanna who reviewed the mishna: Do not teach that fear of sin ceased, for there is still one who fears sin, namely me.”

And now look at our generation, since it has returned to the Land 

as Hashem has promised