Back in the days, everyone could wear avatar. After a while, because of some problem, theymos removed avatar.
When it re-enabled, new rule applied, full member and up can wear avatar. But the newbies who had already with avatar, they remained the same. You can check the accounts. Those accounts are from 2011.
I see one last active account: Last Active: December 23, 2017, 11:45:04 PM.
so it's only been one year, the difference, is this, before the rule, Merit, or new system is implemented in 2018
The account was created in 2011. Avatar was re-enabled in 2015. I have already linked the post.