rov1200 -
Yes, the invention was well-proven into the 80's - I remember as a boy seeing it and its potential applications on 'Tomorrow's World' on the Beeb.
'Well-proven' does not mean 'Significant'; however. Which, I repeat, is the overriding qualification. Post-It notes are HUGELY well-proven and (technically) worthy of Nobel Prize consideration and also have been in use for longer than fibre-optics. But not really 'significant' in that they were really just bits of paper.
And while it was being successfully used by industry in the 80s that doesn't mean it was significant (see also Telex machines, whiteboards and Reaganomics. And also Post-It notes!).
It is only now that fibre-optics are demonstrating their potential beyond the copper wires they were replacing in the 80's, and showing their SIGNIFICANCE. In the 80's their main reason for use was the quality of signal compared to resistance-prone electrical wires. To go back to Tomorrow's World in the 80s, they were first touted in terms of hiss-free telephone calls. Now, it is their exponentially greater capacity for information transfer and communication, or to put in other terms, the Internet explosion.
While I share with you the desire to push the U.K.'s admirable legacy in the technological revolution that started in the second half of the 20thC and is gathering pace in the 21st, I can't agree with your concern at any Caltech or US bias. The awarding committee is in Sweden for one thing, and even for awards given to US scientists they are for work done 30-40+ years ago.