Godzilla survives both the pressure and decompression attempts but is injured. That’s when Kōichi enacts his final plan. He had a kamikaze plane repaired by Sōsaku, deciding that, if all else failed, he would fly the plane into Godzilla’s mouth and detonate it, thus sacrificing himself to save Japan.

The final frames of the Godzilla Minus One ending show a chunk of Godzilla's disintegrated flesh sinking into the sea, but as it does, it begins to bubble. Throughout the movie, Godzilla showcases extraordinary regenerative abilities, and the implication is that a new Godzilla may evolve from the piece of flesh.

The massive decrease in Godzilla's physical strength is best exemplified by Godzilla Minus One's ending. A bomb detonated in his bomb destroyed him from the inside. While the plan wasn't treated as something simple or easy to pull off, it shouldn't be forgotten that it was executed without the government's help.