There is a problem here, but not what the OP was saying.
As more coins stop being used we become more unsure of the total market cap of bitcoin because we don't know if those coins are actually lost or simply not being spent.
What if there is a 1 trillion dollar bitcoin economy but 20 of the 21 million coins are considered "lost" because they haven't participated in a transaction in hundreds of years.
But actually 4 million of those coins are simply sitting in a misers wallet.
One day he decides to spend them.
Now suddenly the number of bitcions increases by 5, causing everyones bitcoins value to plummet by 80%. This would be a huge disaster.
So as you see, as more bitcoins become "lost" the value of a bitcoin becomes more uncertain.
You are correct and great observation, this will be a very serious issue as time goes by. If millions of coins enter the market at once it will cause the value to plummet. It is important to know the number of coins that are in the system. Maybe the Devs can come up with something.
