Why do you think we would have had to find other markets? "no more money to make in the crypto world that would have lost its icon." BTC and other currencies are here to survive. That's why it's called decentralized. I suggest you to read and think deeply about what's written on the whitepaper.
BTC and many altcoins will exist. Their prices will change, maybe their unit price will be very low but they will always survive. I can see this fact makes many people unhappy, but you must face it.

If you have a better argument, please post it.