OK, I hope my question doesn’t get misunderstood, I can see how that could happen.
Just a product of overthinking.
Idea is that we can live fairly easily even with some diseases/disorders which could be-life threatening. Many of these are hereditary.
Since modern medicine increases our survival capabilities, the “weaker” individuals can also survive and have offsprings that could potentially inherit these weaknesses, and as this continues it could perhaps leave nearly all people suffering from such conditions further into future.
Does that sound like a realistic scenario? (Assuming we don’t destroy ourselves along with the environment first…)
I can, will and has. Push back would be on what it means to be “weaker”.
When we say evolution selects for strength, we mean strength in terms of environmental fitness with regards to propagation, not anything specific to health, well-being or survival.
Our earliest “medical” advances actually left us significantly less robust over time.
Techniques like “not leaving the sick or injured to die”, “blankets”, “carrying food and water” and things like that.
Over time, that led is to continue with bigger brains, longer gestation, more care for the mother and infant before and after birth, and old people.
This led to a spiral of smarter, more educated, more cared for people who were able to pass on knowledge between multiple generations.
None of that could have happened if we hadn’t started caring for less robust people, like old man Greg with the bad leg, scary stories about snakes and knows all the berries, or Jane who is somehow so pregnant she can barely walk and who’s last kid was born with a massive cone head and no kneecaps.
What makes us unique as a species is that we have a much larger ability to influence what exactly defines environmental fitness than others.
When we develop new medical treatments, we are potentially making ourselves less robust going forwards, but we’re also making it so that particular thing has less weight in determining what “fitness” means for a human, and more weight is put on “clever” and “social”.
Natural selection selected for a creature that can’t opt out of the game, but can bump the table.
So we will inevitably allow a genetic condition that’s currently awful to become benign and commonplace.
We’ll also keep selecting for smart, funny, social and dump truck hips.
My biggest contenders are diabetes, gluten intolerance and hemophilia. They all used to be death sentences, and now they’re just “not”. There’s also the interesting possibility of heritable genetic treatment becoming possible, which puts a lot of what I said into an interesting position.
We’ll probably keep selecting for those big hips though.