How realistic is it for people to work late into their 60s?

-All depends on the Job, If you work in a nice warm office, Without a lot of stress, And are fit and able working up to 70+ could be done by many active people.
BUT;
If your working out in all weathers in Building & Construction, you will be lucky to keep going to 60, after that you might well be Dead.

If your sitting at a desk job yes, and they do appearing to be quite happy in certain offices and i wonder as to why

As Paul61 says working out in all weathers would not be good for anyone 60+ and know some 40+ who couldnt hack that and others in their 50s now completely screwed due to 30 years on their knees as either brickies or plumbers.But that's ok, as walking 10 miles a day around amazon should do you good some say

I know a few people/friends who are still working as gardeners/handymen in their late 70s/early 80s.  It tops up their pension and keeps them fit!

My grandma worked in Service until she was 73 and only retired because her employer (a doctor) was retiring.

Most of her working life was spent in the Wash House and the NHS.  Her bodily weight never exceeded 6½ stone!

Other examples

https://www.businessinsider.com/longest-living-people-working-2017-5?r=US&IR=T

https://www.wndu.com/content/news/Indianas-oldest-employee-retires-at-102-567627291.html

https://www.nytimes.com/2019/09/26/nyregion/anthony-mancinelli-dead.html

Depends on an individuals physical state, I don't know any in their 70s or 80s that work or even want to.But that's only the 5or 6 I do.

I'd be more inclined to use a hobby if I could to supplement my pension. But good luck to those who can or choose to work until they drop. The idea is to retire ASAP as that's what we've all been fed. Turns out only 10% can afford to and we know where they reside.

I feel the tory gov, like to rely upon the idea every one is working well into their box so to speak. But reality, stats etc reflect a totally different story. 5-8% of over 50's can't and don't find work. The ones working doing a job a few days a week in B & Q for example are likely to be mortgage free, have a nice personal pension, maybe a nice redundancy payoff and carry on building upon.

It's a bit like the myth all work is good for you when leading psychiatrists say its not. That's why people end totally pissed off most of their lives stuck in dead end jobs with poor pay and bad conditions. Those aspects are certainly not conducive to living a long or any fulfilled life. Some also have no choice.

How realistic is it for people to work late into their 60s?

I am not privy to all the data regarding health etc., but I think more people are living longer and healthier lives.  Many of the people near me are elderly (65+) and seem to keep very busy.   A neighbour was laying a new drive after a  

I call them the fittest person in our town!  S/he has had another and is still beavering away in the garden.

There are insufficient rewarding and well paid jobs for the 18- 60 year olds, so it probably not realistic to find a high percentage of people working in their 60s paid or unpaid.   However, many need extra money to survive/other reasons.

Yes, some live longer but as to how many live fullfilled and healthy lives. And what one finds to be fullfilled in could be another's nightmare irrespective of income. I'm in my later years, have multiple medical issues and was very fit for my age. Somethings come up and bite people when their not expecting it. Chronic illness, divorce, berievment leading to a world of depression.

Had four friends already died between the ages of 30-39. Life is for living not living to work as some like to do. One thing as many should know as they age, you find a truly new perspective with the meaning of 'life is short.' I'm in my 60's multi skilled worked in a high tech trade for thirty five years and been out of work for 5 years. Would I be better off working doing some menial job for minimum wage with the job satisfaction equating to zero... No.

I would have thought many would like to escape the rate race in their older years. I will have to hope and pray my investments quadruple over the next ten years, if I get to see that. That's my experience and not a joyful one

If not will be me Vegetable patch and home made beer would also be great to be self sufficient though.

There is far more to life then just working, paying tax, then dropping dead just short of retirement, This is the Preferred Capitalist Model, with full support by DWP, But thats NOT What Life is all about, Im 68 and Forced to work Part time with a Crap State Pension, and Stopped Pension Credit & Housing Benefit, But Its getting to the point Where Heavy Physical work is Getting Impossibly, So Have had to Find "Alternative" ways to Earn, Buying & Selling on e-bay is one way, Other good ways to Earn come under Illegal, But for many of us there is No Choice.
And While the rich Parasites keep voting Tory, we will Cont Living in the "Black Economy".

There is another side to this story, if you like me and used to do a physically demanding job and when it started to get a bit much for my old joints, I decided to have a career change. So I return to further education and did some voluntary work to gain some experience in this sector. So I thought I would be able to get a job in this field, as it was less physically demanding of a person of my age. However, the trouble seems to be with the recruitment/hr departments not being able to see that you have transferrable skills to offer these firms, as well as your age seems to be a problem.  If only I knew when I was younger that my old career wouldn’t last me until retirement, I would have thought twice about going into this sector of work. So yes people can work into their 60’s, however, a lot depend on the type of work. Yet as I found out having a career change isn’t easy as it used to be, when you get over a certain age?