IMO there is no "too late". If you buy now then yes your purchasing power will probably increase dramatically over the years, but even if adoption saturates Bitcoin is still a worthwhile asset to buy / earn due to all of its other wonderful properties.
Put another way: Suppose price stagnated such that it kept up with inflation but no more (~7-10% PA). I'd still buy it like a madman. It would still be superior and less risky compared to cash, stocks, bonds, buy-to-let real estate...
Was a 18th century worker ever late to gold?
There is no day where I will ever stop buying / earning Bitcoin.
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