New research reveals longevity gains slowing, life expectancy of 100 unlikely

Genetics required. Natural evolution has zero interest in old people, so there has been no evolutionary pressure to extend lifespan. Possibly even the opposite.

We could apply that pressure, either through selective breeding over generations, or through direct genetic modification. Maybe we aren't quite there yet, but it won't be long.

Experiments on insects with selective breeding have easily tripled lifespans. How well that would transfer to mammals is hard to say, but a substantial increase is certainly possible.

In modern society there is little evolutionary pressure to extend lifespan, but that's a very recent phenomenon. If my parents watch my kids and do the cooking so I have more time to hunt or work the field that improves the survival chances of my children, and my children share 25% of their DNA with their grandparents. The grandparents living a long productive life is good for the survival of their grandchildren, and thus for the reproduction of their DNA, causing evolutionary pressure. It's mostly the unproductive years (dementia, debilitating illness, severely limited mobility) that are a detriment.

You could argue the same forces are still at play at societal levels. People around the age of 50 have a vast economic impact, having accumulated experience and relationships over many decades. And the average age of soldiers in Ukraine is somewhere around 40-45. If one country had a population that stayed at the mental and physical fitness of a 50 year old for another 20 years that would be a drastic advantage, both in terms of skilled workforce and in terms of military capability. Even just another 5 productive years are a big deal in a world where the time you spend productively working is about twice the time you spend "growing up" and getting an education. And my nation doing well means my children can afford more children, spreading my DNA, making it favored by evolution

Not an expert by any stretch of imagination. But it seems to be that not only is there almost no selection pressure on increasing lifespan, bc of medical advances in healthcare there's also less evolutionary pressure on reducing diseases and infertility (i guess there should still be substantial health related evolutionary pressure from sexual selection) in modern society. Why shouldn't we expect long term deterioration of fitness of genome similar to the deer in Yellowstone before reintroduction of wolves?

Mick Jagger had his most recent son at the age of 73. Today, that's an anomaly, but historically, older men fathering children was not at all uncommon (73 would probably be an outlier, but successful men were fathering children well past the age when women can no longer bear children). That would exert significant evolutionary pressure for men to have longer lifespans.

Watch out for news such as Jagger's , Bernie Ecclestone etc.

We never know if it's their or not.

Famous people are just people who are famous and while the prenup rates are high, people who actually do the DNA test for paternity purposes are low as they are in the general population

Sure, but your average 50-year-old already had their children. They have passed on their genetics, good or bad. No evolutionary pressure.

The life-span extension experiments I have read about specifically only allowed older adult insects to reproduce, pushing that age later and later. Adults that died early did not reproduce. Massive evolutionary pressure.