I completely disagree with this statement. All the typical later model aircraft you will find at flight schools and clubs have a pretty comprehensive set of procedures for the likely emergencies and they all specifically cover the cabin fire emergency.
BPF, that is true but not everybody has a later model. My S2A POH includes emergency checklists for in flight engine restarts and freezing of the pitot-static head, and that's it. The S2C handling notes I have do include engine/ electrical fire checklists.
Interestingly it suggests if the fire doesn't go out or you need electrical power to continue the flight, switch the master switch back on and then start pulling CB's until it goes out. For an engine fire it suggests using a higher glide speed to find an airspeed which provides an incombustible mixture, then if it doesn't go out and you have a parachute with sufficient height remaining, it suggests you jettison the canopy and leave the aircraft!