Despite my wife believing otherwise I can actually do two things at once and with the PTT on the control column I'm confident I could slip out s mayday call of some sorts whilst working to safe the aircraft and myself (inc. pax). It's always good for investigators to hear of a mayday call so they can immediately discount certain scenarios, plus rescue as above.
I've heard so many times that the crashed aircraft was found up to a couple of days later within close proximity to the departure aerodrome because there was no radio comms.