What does Rava limit the machlokes to? Where do Tanna Kamma/Chachamim disagree, and where do they agree?

Using this pasuk https://www.sefaria.org.il/Leviticus.23.41?vhe=Tanach_with_Ta%27amei_Hamikra&lang=he&aliyot=0, what's the reason for their machlokes?

What is the reason that they both agree that a dry esrog is pasul, invalid, based on the same pasuk?

The Gemara then begins to challenge R. Yehuda's view that a lulav does not need הדר/beauty. What source does the Gemara bring to prove that R. Yehuda holds that a lulav needs to be beautiful? Be specific with your quoting of the source and explain how this leads the Gemara to think that R. Yehuda requires hidur in lulav.

What does the Gemara say to deflect/push off this proof? Explain the logic of the Gemara's rejection of this attack question.

Are we happy or sad at this point and why?