Background risk of death from non-natural causes are listed as 1.6 per day; many of those non-natural causes do not exist in an airplane cabin (e.g. you probably aren't going to be murdered because no one has anything more effective than a plastic spork, you probably aren't going to kill yourself, you probably won't be hit by a car). So it seems reasonable to say that being inside an airliner cabin is safer than being outside of one.
Also, this is probably confounded by many super-old or super-sick people not choosing to fly - if you are in an airliner, you are probably healthier than the average person.
Except for the occasional murder who has access to the flight controls.
If someone said an event happens “occasionally”, I would expect it to be significantly more frequent than 1/300,000,000.
Powerball lottery odds are 1 in 292 million. I wouldn’t say that I “occasionally” win the lottery when I buy a ticket!