This is the allegorical world we live in.
Transhumanism threatens to make it literal.
There is a pretty big difference between using tools and altering oneself. Adding cyber-implants is already pretty sketchy. Now wait until someone think that feeling negative emotion is crippling, or that we should become "smarter", and create humans modified like that, and enjoy the results.
We've already altered ourselves. My communicating w you this way over decades has altered my brain and body and neural pathways.
There was a study of London taxi drivers showing their hypothalamus was larger than average due to memorizing city streets (perhaps nowadays due to cheap Sat nav on smartphones that wouldn't be the case). I'm sure my thumbs muscularity has altered since I got a smart phone in 2015 and my brain much more so.
Obviously genetic engineering is a whole nother level but it's coming, humans are tinkerers. It could be dystopian depending on who's in charge but that's how it always is anyway.
Negative emotion is crippling, pretty much all violence and general harm (from physical abuse to being a dick on the Internet) is caused by someone feeling **** and taking it out on another person. Being overly fearful, suspicious and reactive made sense in our ancestral environment but if we could tweak our baselines of fear, reactivity and pain why not?
An argument is that it would be human life more flat but as David Pearce argues that's not necessarily the case. A "hedonic setpoint" between say 20 and 50 offers more of a range between -10 and +10.
You could literally be burying your mother and feel sadness but also immense joy at the memory of her life that we can't even imagine w our African savanna brains (let's say level 20).
Another argument is that you need deep grief to appreciate the good times but chronic depressives experience grief all day every day and don't have higher peak experiences as a result. Chronic pain tends to lead to more chronic pain
But no doubt things could turn very dark if an uninformed and desperate public allows big business to play around w their brain.
As a child of the 80s and 90s labelled w ADHD and depression I got my brain played w during my developmental stage w all manner of drugs.
In reaction to that I became a bit of a hippie, skeptical of all drugs and the medical system in general, prone to naturalistic fallacies.
But the problem wasn't tweaking the brain, it was doing it willy-nilly and motivated by profit (for pharm corporations) and behavior suppression rather than actual subjective well being.
Anyway, time will tell what happens.