"The lost of Lexington lead the US Navy to figuring out it might be a good idea to flush and fill the aviation fuel lines with CO2 when an attack is inbound."
Except that that would not have saved Lexington, as her avgas storage tanks themselves were compromised by the torpedo hits on the port side and gasoline mixing in with the water flooding into the ship. Where that water went, the gasoline went.
The only way to have mitigated against that would have been to completely flood the port side spaces of the ship with CO2, which would have made them uninhabitable.