I think Jagex simply does not care.
I have always thought it must be so easy for Jagex to just spawn items, and therefore would be able to reimburse players for unfortunate situations like that. I know their policy is not to do this because then everybody would be 'claiming' to have lost items or been hacked, but don't you think Jagex would be able to keep records of stuff like this??
If you lose something due to your own stupidity, thats your own fault. The people I feel REALLY bad for are the ones who fall victim to glitches in the game that should not have existed (dueling glitches, the falador massacre POH glitch etc.) and lose MILLIONS if not BILLIONS worth of valuable items, aswell as occurences like when Jagex resets the server back a few minutes (has happened on rare occasions). Imagine being at corp and getting a divine or elysian sigil drop, and then the server is reset to 5 minutes prior and you lose all those millions, all due to some error on Jagex's part that is out of your own control? I have major sympathy for those people.
People who get hacked are sort of in a grey area in my mind... Getting hacked must absolutely suck, and losing all your shit. But tbh, its not that hard to protect yourself from being hacked. I have NEVER been hacked before because I am safe and smart and I keep my computer clean. It is absolutely RIDICULOUS how many people get hacked nowadays, I literally have atleast a small handful of friends every month who mysteriously get 'hacked' and lose all their shit. I don't have as much sympathy for these people as they are most likely just stupid and don't have a very secure account, have been clicking and downloading random things on the internet, don't run virus and malware scans very often, or gave out their password somehow. So I'm a little skeptical about the whole 'hacking' thing... Some of these people deserve to lose their items just so they can learn a lesson and be smarter and safer from then on.
