There is a saturation curve and scalability issue. A company's market cap takes lots of effort to go from $50M to $50B or $100B, that is 1000 or 2000 times. There are lots companies with $50B market cap, there is not single one with $1T not to say, $10T. It is due to scalability issue (what is scalability is another topic of research). If BTC reaches $100K (10 times), its market cap will be $1.7T and $1M is $17T, that is absurd (total GDP of US). **It will probably not happen (BTC $1M a piece, $17T Market Cap), growth is probably in the better altcoins just due to scalability issue.