Not suggesting people go off and die, or be thrown off a cliff. Rather that they consider there are some downsides to society at large if they unnecessarily work late in life. FWIW, I was responding to the question "why not? [keep working]".
Older people helping to make more products/services is a downside to society at large?
I would understand if “working” was a competition for limited resources. But if it is, in fact, a value generating activity, how does it harm society at large?
e.g. Having more doctors work until later, if they are capable, is not a net positive for our society’s ability to provide healthcare?
Now advances in tech may continue to increase demand for workers elsewhere, once training and workers catch up. Or maybe not as much as roles are lost.
Posted a similar request elsewhere, but I think you need to substantiate this claim.
Furthermore, if you're claiming that tech destroys jobs in the general economy, then the consistent position would be that young or old should stop working in tech, not just older people. But the research I've seen shows that tech jobs generate non-tech jobs on net.
I hope you're never old with people around you that think the same as you think now. Either you can do the job or not.
As to immigration and women and others, it can be argued the end game of every able bodied adult working until death is quite dark -- even if it begins with most of them finding some enjoyment in it.
When I'm old I hope my family encourages me to find joy and meaning outside employment, once the finances have been secured for retirement.
Someone experienced continuing to work in tech is a net benefit to society; they contribute way above median taxes and their economic activity generates jobs. It's not zero-sum; the more people working in tech as senior engineers, the richer society gets.
The only case I think you could actually point to net downsides is that within tech, it's possibly easier for a more junior to get a job replacing a more senior when the latter retires, from reduction of competition. So from a selfish perspective of "I want your job" sure it makes your life easier if a senior engineer retires.
I'll put a [citation needed] on your claims around downsides to society and leave it at that. Judging by the downvotes it seems others don't agree with you either; if you want to persuade people I think you need to provide some concrete evidence.