It's neither art nor the box office — it's a months-long campaign war where studios with the biggest PR budgets and savviest lobbyists buy gold statues.
The Oscars are about prestige: Hollywood crowns the films it wants remembered, not the ones that sold the most tickets. Box office gets money; Oscars grant legacy.
It is purely industry politics and expensive PR campaigns. The best film rarely wins; the studio that spends the most money schmoozing the Academy does.
Oscars are pure industry politics—studios buy votes with campaigns and schmoozing, not talent or ticket sales.