Death is normally the end of it all, but fortunately in games, you get many more tries. In MMOs it's even further down on that scale. Certainly if at some point RuneScape flashed "Game Over" in your face, forcing you to start over completely, you'd have quit by now.
So where are we now? Not long ago, dropping to zero hit points would cause you to drop everything you had on your person to the ground, save but a handful of items, depending on prayers and floating skulls. After that, you would respawn in Lumbridge, restored fully to health, with but a few minutes to get your stuff from the ground before it became available to everyone. Only in the Wilderness would your stuff become visible immediately to the one who just killed you.
After quite a bit of turmoil on how death worked exactly during the Wilderness removal period, it was finally settled on not losing anything at all as long as you could reach your gravestone in time.
These days, not even Bill Murray's industrial bout of self-destruction and suicidal tendencies as seen in Groundhog Day can make you lose a sizable selection of your items.
Not only do you keep some items as a result of the usual three and the prayer that protects an additional one, but a whole selection is automatically kept no matter how you died. And they're going to add the opportunity to allow you to keep one more item when Divination is finally here. Only the location seems to matter, as you can still lose everything in the Wilderness.
Now, besides allowing you to pick what appears in your inventory and Gravestone, you also get to pick where you're going to respawn. This used to be a big deal, as you had to complete several quests to unlock Falador and Seer's Village as spawn points, but today that's different.
It remembers where you've been, allowing for you to bank quickly and retrace your steps in order to retrieve your items from your Gravestone.
So, is there any risk at all of losing your items? Some locations might not be able to be reached in time, such as certain God Wars Dungeon Boss rooms. But you could always have a friend bless your Gravestone, allowing for it to sit there for an hour. This is way too much time to retrieve your goods.
No, the only true death and loss of items comes when you get disconnected from the game.
I'm sure there is a joke about The Matrix in here somewhere, but all I can come up with is the facial expression of someone who knows that he or she is about to be disconnected. It's the same look you have on your face the very moment you realise that every attempt to make your character do something (anything!) results in that same still-life screenshot.
In my opinion you should be allowed what you get to keep before you're in any danger of dying anyways. Choosing what you take back with you to your spawn point requires for the laws of physics to be suspended, because if time stops, I'm pretty sure YOU can't move either. Then again, choosing what you take from your own corpse is a bit morbid when you think about it. At least the visit to Death's office seemed believable.
Speaking of meeting Joe Black, I also find it hard to believe that you can only die from damage these days. The only time you die instantly and accidentally without any damage inflicted upon you is when you collapse a cave around the Dagannoth Mother. Whatever happened to disease? Or setting someone on fire? Even poison isn't very effective these days, and far from worth the hassle of making it.
Also, if you're not prepared for a fight, someone stabbing you with a knife, even if you're in full armour, is going to kill you just like the half-assed attempt of the bad guy in "I still know what you screamed last Halloween in Texas, when you saw that 13 Elmstreet was the wrong destination" (seriously, I always root for the stupid ones to die).
The point of meeting your maker was to make you more cautious, because it meant you would lose valuable items and you had only a limited amount of control over which items those were. That has gone, and it feels kind of like playing in god-mode now.
It doesn't look like this is going to change though. The trend of eliminating the dangers to a player has been systematically continued over the course of history. But who knows? Perhaps they will one day come up with a "hard-mode" world where you risk losing everything you have on you, in exchange for increased drops.