The article talks about quantum computing possibly enabling a 51% attack on Bitcoin. If anyone is worried about 51% attacks, don't hold Bitcoin Cash. It's vulnerable to a 51% attack right now.

Bitcoin Cash typically takes 10% of the combined BCH+BTC hashpower. A malicious miner could mount a 51% attack on BCH by shifting mining power across from BTC, mining BCH less profitably than BTC thus driving swing miners over to BTC, until they, the malicious miner, is doing more than 51% of the BCH mining. The malicious miner would need to control about 6% of the total BCH+BTC hashpower to make a successful attack.

However, I do not think it will happen - who would be mad enough to do it!

Except possibly North Korea. Or Iran. Or [insert your favourite bogeyman here].