The rich people knew how to over evaluate BTC in Dec 2017 by using loads of marketing tactics (FB campaigns especially) and to use USDT (they were buying BTC with USDT massively to create an artificial demand and increase FOMO) to pull in people that didn't know how BTC works.
These guys already made a huge profit in late 2017 - early 2018. No need to worry about them
Surely those who are investors, are gonna be rich as you said already people had huge profit than even without earning they can live good life till the price recover the fall of 2018, I know very soon it will be overcome the loss as experts have predicted the market to be high in 2019 and 2020, so lets see what actually happen, I really wish to be rich in future.These guys already made a huge profit in late 2017 - early 2018. No need to worry about them