A very unlikely scenario ( perhaps not so unlikely in these days of terrorism?) , but if there was no-one else you'd have to try. Better than sitting there waiting to die !

On one 9/11 flight passengers fought the terrorists,probably after they had murdered the crew. If they'd won, one of them may have tried to land the plane.

Also there are reports from the F16's of people trying to take control of the recent Cypriot airliner that crashed.

I always thought that one of the biggest problems would be to make radio contact with the ground/other aircraft for talkdown etc. . I never bother with figuring out how to use the radios in FS, maybe I should ?
One official commentator made the point about passengers not being able to use the radios in the Greek crash.

I think that most experienced simmers would have to take a stab at landing a light type. ( It has happened not too infrequently that a single pilot has had a heart attack, for example,  in a light aircraft leaving his passenger/passengers to their fate.

I would probably try.....but due to my age they probably wouldn't let me.......