How many offices still have a typing pool? When was the last time you spoke to a switchboard operator?
I don't think it is so outlandish to question what happens next. I was recently in Dubai and the Metro system was very pleasant- fast, efficient, comfortable, cheap. And apart from a couple of ticket inspectors and the guy sweeping the platform, there were no staff at all. Everything was computerised. Far from it being a dystopian future, the truth is that train drivers themselves will also become obsolete due to technology much sooner than they would like.
The question is not whether technology can replace people- it already has- the question is whether we want it to.
Leaving aside some people's desire for a minimally staff-less railway, the Dubai metro was built in the last couple of decades, well most of the country was built in the last 50 years.
I'd suggest it's a lot easier to build a railway from scratch, fully contained, with automation and at the time with a very healthy oil revenue to fund its construction, using labour imported from India etc who are paid poorly, live in atrocious conditions and have to suffer scant regard for health and safety.
Compare that to bringing the UKs largely Victorian designed and built rail system up to the standards need for full automation, then I think it will be a while.
It probably will happen eventually on a more widespread basis, but I think London bridge to Kentish town (approx) on thameslink is the only stretch of the UK at or near automation.
Yes, we're living through the technological revolution where computing capacity is expanding exponentially and becoming much cheaper and the railways won't be immune to those changes.