Yes.
There was NO place to hide. Once it was determined fighter strength was too overwhelming, we should have re-grouped, reassessed enemy strength, then either blasted the Japs to Kingdom Come, OR skipped it.
Iwo wasn't essential -- it was a convenience.
Well, since we won, it was not 'overwhelming' was it?
Sorry, but the costs of a defeat at Iwo, would have been far higher then the costs of the win.
Once a decision is made to fight, it is almost always better to go full throttle, then to turn and run, as you suggest.