I hope this doesn't go Botan route.Wooo best girl (boobs) won. Oppai-ship has finished its voyage and returned safely.
Seriously.. Thats the only justification anyone had for Yoshino being best girl. Boobs... We don't deny it. We like, what we like. We're simple readers.
Let's be honest here, this kind of stories had only three kinds of endings:
Aki's ending - Stereotypical main girl wins, issues & misunderstanding resolved and mutual love.
Yoshino ending - The underdog heroine. The "support character that evolves into realizing their own feelings" trope. An uncommon scenario but not that rare.
The god-forsaken-everyone-is-happy-status-quo-no-resolution-ending - Everyone would have flip the table if this was the case
It really was up to the whim of the author which way the tree will fall and its just decided to not go to "oh so conventional main girl route".