I think the requirements are fair and well adjusted. I do understand where people are coming from, but three years is a long time. I don't consider three years a "hiatus", that's basically being completely inactive. It's necessary to do something after ten years since we never had IGN wipes before.
I'm worried about one thing though, this news not reaching the inactive players. Inactive players don't pay attention anymore and their e-mails accounts might not exist anymore. I'm sure relatively many of them would log in just to keep their names if they knew about this, though sadly there isn't much to do about that.
There will be returning players MapleStory Mesos complaining about losing their IGNS due to not knowing about this, I can already see the threads roll in. Hopefully they will understand that being inactive means missing out on important changes to the game.
Just because you all know 2-4 people who came back after a long period of time like 4 years doesn't mean it's common and the name changes should be relaxed.
Ensuring that current active players can get a more meaningful ign and that future players can have a much larger variety of choices comes before catering to people who quit 3+ years ago and may or may not ever return.
The level isn't going to change regardless, if you really want to make sure your friends don't lose their igns then I'd suggest contacting them and letting them know. If you don't have contact with them and they've been gone for 3+ years then I don't see why it matters.