Why “mij” <> “ni”

“Esperanto is a very logical language, with complex words derived from simple roots in a highly regular way. Why, then, is it not possible to form plural pronouns by adding -j to the singular ones? It would make sense to say ‘mij’ instead of ‘ni’, use ‘vij’ for the plural ‘you’, or speak about a group of women as ‘ŝij’.”

Read more: https://jakubmarian.com/why-not-mij-vij-lij-instead-of-ni-vi-ili-in-esperanto/