With good KYC regulation and enforcement many "hacks" can be mitigated. The Bitgrail hack, for example, was performed by customers taking advantage of shitty code. Presumably they know which accounts withdrew funds, but if they knew who the customers were that belonged to those accounts, they could go after them. This stuff is a big reason why I support exchanges being regulated as money transmitters.
Or even worse in some cases, someone that maliciously "burns" all of your bitcoin irrevocably destroying it forever by sending it to a bad address. Even if you catch the person that did it, that bitcoin is gone forever, and you can't just bring it back without concensus of the extreme majority of all miners and users (which isn't going to happen in bitcoin, it barely happened in Ethereum when it was much smaller with the DAO hack)
For starters, cryptocurrency exchanges need to know the crypto they trade with VERY well. It's an area where the law won't help you if you mess up. If someone steals a bunch of bitcoin from your exchange, a police report isn't going to get it back, it's gone for good.
Then add in that crypto exchanges are 24/7 (not just during business hours), and I'd argue that scaling them is much harder, nobody knows if cryptocurrencies will double (or more) in usage over the next few months, or if they will halve (or more) in that same time. A single runup could cause 10X the trading activity overnight.
I do think that we need more legal, regulated competition in this area, but I don't think for a second that the answer is Nasdaq trying to shoehorn cryptocurrencies into their current systems, they are just too different.