Your points would have made sense if people actually did what you were saying before we removed the clan. People did not dedicate that much time to become the Uchiha characters and caused a lot of the issues with reseting you are trying to say bringing back the clan would fix.
If they want to start with a clan they know, there are dozens of popular named clans from the anime that outnumber Uchiha Clan. Akimichi, Nara, Yamanaka, Uzumaki, Namikaze, Senju, Hatake, Shimura, and that’s just some of the leaf clans. There are also very popular named clans in other villages too.
Exams aren’t being filled up because people are sad they can’t pick Uchiha, I really don’t know how you can come up with that conclusion. If you haven’t noticed, we have no one to host the morning exams a lot of the time and so exams have not been hosted on schedule. This causes issues with player retention.