Why Hiryu surviving Midway would not reverse the Pacific War

What if Hiryu survived the Battle of Midway and returned after repairs?

Japan would retain a carrier and more aircrew for a while, but the United States' much larger carrier-production pipeline would still overwhelm that advantage.

Hiryu returning after repairs would preserve a carrier and some experienced aircrew, giving Japan a real short-term benefit. It would not cancel the expanding pipeline of American Essex-class carriers, aircraft, and trained personnel. The comparison is Britain absorbing the loss of Hood while additional King George V-class ships were entering service, whereas Bismarck represented a much larger share of Germany's usable capital-ship force. Hiryu's survival changes the tactical balance for a time without reversing the industrial imbalance. Long wars reward the side able to replace losses and sustain construction at scale.