If p2p cash can't scale, it's hard to consider it as sound cash. At least it should scale a lot more than Bitcoin does now. Bitshares and Steem are great examples how it can be done.

And the problem isn't exactly scalability, it's the incapability to make decisions on time. Governance model of Bitcoin sucks. If Bitcoin ever wants to be widely used cash, it should make big reforms on it's decision making process – which is, as I said, just chaos currently.

From a security standpoint, I think very much that sound decision making process is really important. If there is no clear way of deciding things, it's hard to react to different threats.