Well, AOL was pretty successful for a short time. No reason private blockchains won't have some success too. Some people even still have aol email accounts.
AOL is quite a success in the USA.
I know in some countries they have been a failure, but AOL is far from being an almost dead enterprise.
And private blockchains seems like a paradox, considering that the nature of the blockchain is being decentralized. Maybe some technology inspired in the blockchain, but with some modifications. Gonna watch the video carefully when I have time
The NXT team are working on its 2.0 iteration called Ardor. That will be able to deliver "private" decentralized blockchains as child chains.