Netherite tools should float in lava like items do in water, the tools and armor would bounce away from the player’s point of death so they would still lose some of their gear.
How to recreate:
Place down lava or find a lava pool, then drop a netherite item into the lava and watch in bounce randomly.
Thank you for your report!
We're actually already tracking this issue at MCPE-65372, so I will resolve and link this ticket as a duplicate.
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