But you will have a video of your death.

Well. Your loved ones will.

What if the drone has a 2-3m acuracy of the position? At least in ski resorts the bystanders can immediately rescue the person. Off tracks, it often happens that 1 person is aside of the snow corridor.

That level of accuracy would be hard to achieve. Most radio signals (eg. BTLE) don't travel well through water (eg. snow).

Additionally, if you've ever dug someone out in the field (or practiced doing so) it takes a lot of effort to move snow. Being within three meters isn't good enough.

"At least in ski resorts the bystanders can immediately rescue the person" - someone who has never been in or experienced an actual avalanche.

No they can't.

While not a bad idea, I think the existing avalanche rescue gear is better suited.

The drone would hopefully though still be hovering above you so would help any people in your group find you faster

Maybe avalanche wasn't the best example, but still, a robotic lassie seems like it would have uses!