My main point here is the time variable, and the scarcity.

1 BTC 2010 = 1 BTC 2021?

It is not.

Anyone could mine 50 BTC at 2010 with less than 100 USD. You just had to bought an old laptop, mine for a few hours, and you would get a full block reward.

How much does it cost to get 50 BTC nowadays? You would need to mine almost 8 blocks alone. How much would take cost? Probably something close to 1 million dollars of equipment and eletricity?

Bitcoin is now more scarce than it was in 2010. As it is more scarce now than in 2018.

1 BTC in 2010 = 1  BTC in 2020 is the same as saying 1 glass of water in london = 1 glass of water in the Saara Desert. It is not!

This basic economics. Supply and demand.

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