Fortunately, the tendencies for neatness and build quality reinforce each other.

(Sadly, Sir Ive's obsession with thinness and minimalism did not mesh with actual ergonomics equally well.)

My grandmother (she'd've been ~118, now) taught me to sew. There's specific techniques for turning down interior hems. That is, imagine a jacket: it has a shell, and a lining; I'm talking about a specific kind of hem for material between the shell and the lining. The finish work of that hem had no bearing on the quality of the item — it just demonstrated to the next tailor working on the jacket that you'd spent the time to finish the parts only they would see.

And, goddamn, it doubled the effort for finishing a jacket.

Did the turning down make the hems any less susceptible to wear and tear? Any less noticeable by the wearer?

Nothing. Just extra work. She'd say "you know it was done, that's enough".