1. Predictable BTC loss is destabilizing. Every transaction includes risk of loss, meaning a greater portion of supply that is immobile will grow. No, that's not solved with divisibility. The world cannot have confidence trading it's wealth in 1 million BTC with 20 million sitting on chain immobile. If another million can suddenly wake up because an unknown pool has been hoarding them, it wrecks the market.
With this kind of logic, Gold, Oil or other precious metal should have fallen years ago, there has been many massive gold and oil reserves revealed through out the years, but we can see that Oil and Gold is still relevant. There won't be any problem if 20 Million of Bitcoin suddenly found and send to the market, if the demand is exist, the price will be maintained.