I think something to consider is that to whatever extent governments and banks would want to "kill" bitcoin for the sake of ushering their own token .. they could also just realize to invest in bitcoin.
Like, if they're capable of knowing there is money to be made here, then they buy a position in the existing cryptocurrencies while it is still early.
And then from there they'll have some incentive to want Bitcoin to succeed-- Goldman Sachs would prefer Bitcoin to a rival bank's token if they have a position in Bitcoin but not in the rival bank coin. So they won't perfectly be able to coordinate against Bitcoin, and so I don't think it's something they'll be able to displace, or really even attempt to.. it seems to make more sense get in early and then have a huge position.
And for all we know that's what they've already done. The mystery of who Satoshi is and etc and so on could be less romantic than we often assume. It could be rich and powerful interests carving a stake in what they know will be the future of currency. Which I don't think is a bad thing at all-- it's still a growth and an evolution to something that's better than fiat. It just takes time until it levels out to a less top-heavy world.
Interesting, but in this case I do not believe the banks are interested in "position" but rather in the efficiencies and additional profits that would flow from making use the technology, but one that is designed in such a way that "the banking sector" had control. They would never wish to be at the mercy of "Chinese miners" for example. So the creation of something entirely new would be required - perhaps they will put something in-place simply to transact with other banks, but if they did move into consumer-realm, with the full participation of governments, then they would steal away the benefits of Bitcoin, in the eyes of the average citizen, most of whom are SADLY not interested in our anti-statist, anti-bank-credit-enslavement revolution.
We can not say where they are going with these "experiments", but if ever fiat is threatened, for certain they will go as far as necessary to secure their future. When you compare the amount of money flying back and forth between banks, Bitcoin is not even a blip on their radar at the moment, but they do see the power of the technology, and there is no other group more engaged in trend analysis ... well, besides the insurance industry. :)
Cheers .. I appreciate everyone's very thoughtful comments and feedback!