That could be the case indeed. I'm not sure how the decision making process at exchanges around this topic works. I can imagine there are quite some risks on adding fiat gateways and pair them with blockchains that have not proven themselves as long as BTC or ETH.

On the other hand, if this is deployed on exchanges that have already a lot of pairs, it will allow for a lot more arbitrage opportunities and even more robot trading. I guess in general this raises the 'reserves' held on all exchanges by those bots trying to take advantage of this. Volumes might increase tenfold easily in a short period of time.

Anyway, it will be very interesting to see how fast this develops into the future!