Nobody Will convert into btc risking to lose half of its value in one minute.

Secondly: yes, this will happen. Companies will transform their system into blockchain, saving alot of money. I don't know if that's possible for companies like visa and MasterCard though.

It doesn't matter for Bitcoin, btc won't be a currency until it loses volatility. It will probably be only digital gold. So if more and more blockchain adoption takes place in companies, it will schine on btc.