Therefore, those coins can and should be considered part of the supply.
About 244,000 metric tons of gold have been discovered as of 2021 and around 10% of that is owned by the governments of US, Germany, Italy, France, Russia, China, Switzerland and Japan. NASA's telescope
captured a rare medal asteroid whose gold if brought down to Earth, would make the ounce's worth much
much less.
So is the circulation ~244,000 metric tons of gold? No, but much more than that. Is it realistically effectively possible to reach that asteroid and start moving huge, golden rocks? No. So, why should you assume they are part of the supply?
I know that you can't make heads or tails of which bitcoins are lost. However, you can assume that possibly hundred of thousands won't come into the market due to the same reason the asteroid won't come down to Earth. It's highly unlikely.