Thats rubbish. A quantum computer can't "crack ethereum and bitcoin in1 hour". Bitcoin and ethereum itself can't be cracked.
Quantum computers are no magic machines. And the development isn't furious. While it is true that quantum computers are way stronger
against elliptic curves calculations (like used in btc's key calculation), you also have to consider that there is the possibility to adjust the BTC protocol
to the current needs. Before bitcoin will get 'close' to get 'cracked', there will be an quantum-comuting-proof algorithm implemented, replacing the current one.