Bodies remain on Mount Everest. Why?

No.

There are such things as anti-avalanche devices used all over Europe to stabilize slopes above towns, preventing avalanches from starting. Avalanche control - Wikipedia

Neither of these are appropriate for Everest, which is fine because they wouldn’t work there.

How about a 4 legged robot “horse”? That could easily carry a corpse down. no muss, no fuss.

A biological agent that would operate at low temps and on freeze dried tissue, leaving the synthetic and metallic bits to blow away seems neat and clean. Problem is that such an agent would likely also happily attack living tissue.

Plenty of work being done on robot horses, but they’re not quite ready for active duty yet. Besides, there’s plenty of terrain on Everest that’s not suitable for a quadruped, whether mammalian or robotic. A robo-horse would also need a whole lot of energy to make the ascent and descent, so someone is going to be lugging up batteries or fuel for it.

And then, once more, there’s that pesky question of who pays for all of this.

That’s what we need. A flesh-eating extremophile bacteria.

Zombie virus, then the bodies can walk themselves back down.

Then you WOULD need recoilless rifles or some such once they got down to blast em before the brain feast.

All this talk of helium, robot horses, and zombie viruses is ridiculous. Not feasible at that altitude and who would pay for it?

Here’s a much better idea: each climber carries up a 3-foot section of metal playground slide. Train some Sherpas to weld them together. By the end of a few seasons, you’ll have a giant slide from the summit right down to base camp. Just drop the corpse on the slide and let 'er rip. Wheee!

I find this idea totally unrealistic. Sherpas don´t know how to weld and even if some of them would learn rudimentary skills, thick gloves they are using would make precise welding impossible.

If something like this is considered, it should be a chain of well placed trampolines instead.

Stupid question, but why isn’t burial an option? (Obviously there’s a good reason it isn’t done, I’m just curious as to what that is)

Ever tried to bury something in solid ice on top of granite?

And grave digging is considered an intensive manual labor task even at normal altitudes with cooperative soil.

The most realistic option by far is that every climber picks up a rock and places it on the body until they have a cairn covering the body and this is in fact what is actually being done.

Most of the climbers families are happy for them to remain on the mountain. Cover them with rocks to make a cairn, problem solved.

Options for burial have been covered in several posts above.

Burial up there typically means dropping the body down a crevasse, or sometimes covering the body with nearby loose rock which is only available in a few places where there are bodies.

But you wouldn’t have to dig very deep because there are no dogs, wolves, dingos or coyotes to dig up and eat the corpse.

Even a shallow grave in ice and rock is going to be impossible. Cairn or crevasse are going to be the only options.

Hey if you can handle the death zone enough to get to the top, you could instead not get to the top and bring the bodies a few feet down. While many people are willing to sacrifice a lot to get to the top, the same is not the case to drag the bodies a few feet down. SO we have lots get to the top, and bodies that do not move down.

Seriously? You think people are going to spend tens of thousands of dollars, and then not attempt their goal, in order to move bodies down a few feet? And as has been said, it’s pointless to move them down a few feet unless there’s some coordinated program to get them down.

And again, you haven’t really expressed why it’s so important to move them down. You don’t need to move them down to give them last rites.

I’m not even sure what this means.

You haven’t made a very compelling case for why they should. Suppose you went on vacation to Barbados and, on stepping off the plane, you were told that actually, there’s a pressing need for people to dig graves. You’ve got some free time, right? And digging graves is more important than lying on a beach sipping cocktails, right?