ITSO was out of date before anywhere even implemented it.
In what sense? ITSO specifications were around in the late 90s/2000s, before Oyster.
And the future is "dumb" RFID cards with the ticket actually in a database.
I disagree

For a start, this would require replacing all of the gatelines with RFID instead of NFC readers.
Secondly, phones generally do not support RFID (why should they?) so this doesn't work with mobile payment wallets.
Thirdly, this now requires every device to connect to the internet and centralised databases which is very suboptimal (hence, why bank cards can work offline, why TfL touch-ins/outs aren't instantly updated).
The future is mobile based smart ticketing. Ideally, I would suggest that the tap in/out with your bank card method of transport is what people would prefer (with you automatically getting the best fare, less delay repay etc.), but for many reasons this is not currently easy to implement in the way the railways currently work.
So, we're back at ITSO. A way to load transport tickets onto any ITSO compliant mobile wallet or card, which exists now. And works.
ITSO is probably a good example of edge computing, which is the way IoT is moving right now. It's much simpler and easier to have small, low cost and smart devices which can do much of the processing within local networks, without the need for constant lookups to big data centres.
Ps. we can agree to disagree :P