The cryptos won't collapse, imagine this period as a chance to buy more coins cheap. I think that the most 'big' investors do the same, and benefit of people who sell their coins at low prices. If your investment is made of money you afford to lose, don't sell. I'm sure that very soon all the coins you have mentioned are going to double their prices. If you need them, to pay your rent or mortgage, you have a dilemma.