That will not happen at least soon, because total value of altcoin market is very big. Maybe now is the best time to invest or not, new restrictions are considering by russian government. If the restriction will be approved crypto market get dropped on some %
There are so many things shoulf happen before cryptocurrency is ending because for now i agree that the market cap is so much and will increase again in run of the time. The market cap need to decrease again even so low to make cryptocurrency end.