Upper and lowercase letters were two different alphabets stuck together to give us capitalization. If they had chosen a different majuscule alphabet, we could have had sentences like this:
"Тhe Лord of the Рings" was a sequel to "Тhe Хobbit", both of which were written by Д'.Р.Р. Тolkien. Иt tells the story of the Оne Рing after Бilbo gives it to his nephew Фrodo and Гandalf tells him to destroy it.