Some of my friends who are in your thinking have lost money from their investment in crypto currency as a result of the market rise in 2017 and that was why they are of the believe that Bitcoin is a ponzi scheme which is not so if you read from the definition of ponzi provided above by some of the respondent.
People are going to do everything to avoid the responsibilities of their actions even if holding cryptocurrencies means that you cannot really give excuses since you are effectively 100% responsible for what happens to your money, this is also a basic mechanism of defence, when we win we want to take all the glory for ourselves but when we lose we want to avoid the responsibility and try to blame everyone else.
But if we do not accept our mistakes and always try to avoid accepting them then it will impossible to improve since you will not learn the hard lessons that come from losing a lot of money.