I don't understand
You'd think a nerd's QoL would stay the same (if full NEET shut-in) or decrease, because the lack of social interaction from earlier years would result in more 'life mistakes' later in life (with a bigger impact as well). Too many examples to think of..just imagine a virgin meeting a girl @ ~30, shits not gonna work well
Think one aspect has to be the guys that go full out in their 20's banging the weights or doing extreme sports.
They hit 30 and they tend to drop from there due to injuries or not adjusting to their slower metabolism.
See it over and over guys that where repping the six pack suddenly hit 30 and they got man boobs and a beer gut.
You hit 40 and the back starts to cause you issues if you have been using your body for work(ie. construction).
The nerd has sat idle with his physicality and starts to look better to the lady that now has a slob for a husband.
Husband is couch ridden and his wife starts needing help with her computer so she can facetime with here girlfriends.
Enter the dork and suddenly she sees he has potential and she could groom him into what she wants with a little sexual blackmail.
Also their are more nerds than cool dudes when the ladies come out of their first marriage.
The crying shoulder tends to be a nerd!