It's not just the UK. As someone who is themselves in the same age range, as a hiring manager it's been eye opening to see the clusters of resumes from older candidates.
It continues to boggle my mind how many resumes out there are people who have spent the last 20+ years working on the same set of problems, using the same tech. The reason a lot of these people aren't getting jobs is not that they're old. It's that they've stagnated to a degree I would not have thought possible. Meanwhile there are people out there who are staying relevant *and* bringing extra wisdom to the table. Those people get hired.
What would you look for to see if somebody is 'staying relevant'? Side projects? Personally, I would like to explore new technologies, and am still excited to learn, but feel limited by what is actually needed/required in my day-to-day which is unlikely to change.
It's more just that your day to day *should* change over the course of 15-20 years. What I'm referring to are situations like people who have current day to days that read exactly the same as it did in the early aughts. For instance poking at pre-generics Java to parse XML files, populating some enterprise beans, and pushing to a web page using whatever the heck framework was in vogue back then.
There's nothing wrong with someone turning their brain off and working in that role for 20 years. But they shouldn't be surprised if their experience is completely irrelevant in the modern job market. If one wants to develop new experiences and their job won't provide that over a long period of time (say 5-10 years of employment, not every 6 months!) then it's time to consider the tradeoffs you're making.
In my experience technologies that were popular in the past but are basically dead now are a red flag. Perl, Pascal, Smalltalk, maybe even Java and C at this point, if they don't know anything newer.
Java is an "it depends". Are they writing early aughts style enterprise Java, following early aughts patterns, and using early aughts frameworks? Or are they using fairly modern Java, doing things in a fairly modern way?
I've hired for Java roles in the last handful of years and this was a very bimodal group.
There's nothing wrong with that per se, especially for a company.
I'm only referring to hireability in new roles. If someone is staying in such a role that entire time, especially if their niche hasn't evolved such that it indicates refreshing tech skills from time to time, they shouldn't be surprised if the rest of the world has moved on from where they've stayed.
It continues to boggle my mind how many resumes out there are people who have spent the last 20+ years working on the same set of problems, using the same tech. The reason a lot of these people aren't getting jobs is not that they're old. It's that they've stagnated to a degree I would not have thought possible. Meanwhile there are people out there who are staying relevant *and* bringing extra wisdom to the table. Those people get hired.