Yes that is my understanding as well. In addition to what you said. The developers of the Atos Quantum Learning Machine (QLM) (a computer system that simulates quantum behaviour in order to develope software for a future quantum computer) support the development of an encryption that is quantum resistant. They expect a first working algo in about 1 year. Means, in the future all bockchains and cryptocurrencies have to go through a major hardfork.