In my honest opinion, yes, the whole cryptocurrency market is a giant bubble, it will burst sooner or later, just like the dot com bubble bursted, but the thing is... even though it bursts there will be coins that won't disappear, the dot com bubble bursted and some companies decreased a lot in price, but look at the winners now... google, youtube, amazon, they all won and are now big companies.
So what am i saying by this: Yes, the bubble will burst sooner or later, but there will be some coins that won't die out, we just need to find those that won't die and invest in them!! The only one i'm 99% sure won't die is VET, the rest of the coins i really don't know, i can see some problems in BTC, i can see some problems inETH, etc... So let's just hope we are all investing in the ones that prevail in the end!