I think there's somthing to be said for having a salary structure which rewards long service, but I do think the cut off point is open to challenge.
E.g . is someone who is doing the same work but has been in the job 15 years, really £9,000 better than someone who has been doing the same work for 5 years? Surely, there's a point where long service does not improve your ability at the job.
Given that women find it harder to build up very long stretches of experience - because of caring for kids etc. - extreme examples like that will tend to affect women more than men abnd shuld be open to challenge.
I'm willing to accept a colleague who has been dong it for 10 years knows more than me when I'm in my first few years, but after 5 or so years.... is there really that much difference between our abilities?
I think that's why in most graded jobs, incremental rises tend to stop after 3-5 years, and salaries then become equal after that point.
This ruling suggests that if you are in a job where your colleagues keep getting more money year after year, regardless of ability, and you can never catch up no matter how good you are then it may be possible to challenge your employer.