The very essence of cryptocurrency could be at stake by means of centralization and capitalism, so I wouldn't call cryptocurrencies as indestructible as this is still subject to such schemes that can ultimately result to the destruction of bitcoin. Perhaps right now people are still making money out of bitcoin, but once there's a new fad in which people could also make money from, see everyone lose interest on bitcoin and die. Speculation is what drives bitcoin for now, but once that's over, idk what will, given that almost all people in here are now profit-centric unlike the old days.