I actually think it would be good if they offered 3-4in as standard. For me, 2in extension makes the pendants actually wearable, without that extra length they are chokers on me, i don’t know if you have the same issue. But 3-4in would be nice since it allow for varying lengths. My sa has said it’s because once pendants get too long they don’t look good, but considering the differences in all of our bodies/necks (especially if any men wear them!) it seems like a reasonable accommodation.
I mean, I think they'll allow if you ask, hit its not offered per se. I actually like an pendant to hang a bit lower so it doesn't sit in the hollow of my neck.