People talk about Bitcoin as "digital gold", but in reality it's not even close, and no crypto ever will be. Gold is valuable because there is a fixed natural supply, and throughout human history, across many civilisations and societies, gold has always been worth something - unlike our fiat currencies who's supply can be altered and made valueless.
The problem with Bitcoin isn't it's supply, it's that it's value relies on it's demand remaining high (or at least maintaining current levels). Problem is there is no historic reason or intrinsic value to bitcoin to assume it will continue to have steady demand like gold.
More worryingly in my opinion is that bitcoin's current demand isn't really for bitcoin at all. The demand is to make USD fast. The moment people realise Bitcoin might not give them returns similar to other safe investments, it will crash like all other bubbles do.
I'm not saying people who get in early won't make loads of money, plenty of people made money from the dotcom bubble too, but you need to be smart about it and understand the risk. At $6,500 bitcoin's market cap is far beyond PayPal's which provides a genuinely useful service and processes millions of dollars of transactions every day.