This is still a must have suggestion. With the full release of Age Verifaction, it’s very easy to get verified now, I highly suggest using this as a barrier for forum entry as suggested by this popular post.
I believe verifying a user’s age is a much better way of enforcing entry into the forum.
Clarification of behavior aside, now that the OP had bumped the topic, I now can reply with my opinion on this.
This is by far one of the worst ideas I’ve heard to ever be suggested for the Roblox Developer Community.
I stand with the statement above and I will not change it.
You’re completely inconsiderate and ignorant. for thinking that implementing this requirement won’t affect the roblox developer community in a very negative way.
To clarify, my post suggests that people who are age-verified are automatically ranked up or it boosts your score for being ranked up. Not to block people from ranking up at all without age verification, which I think is much too strict.
I believe that was what my suggestion is, though I might need to clarify this. 
I may be late to the discussion but it is a stupid idea to implement something like this. Doing so would yes, get rid of false +13’s but also kill of about 10-25% of the DevForums. People would be falsely banned because they wanted to see #lounge (Roblox error though) or something. Some people prefer to keep hidden but a huge portion just can’t verify because there school doesn’t give Libary Cards that would be valid of some sort. If this was implemented, then DevForums would loose it’s purpose. It’s for learning and meeting new Developers, if everyone was 16-25 (Since you don’t immediately get a ID card the nanosecond you go 13) then it would be dull and you would get messed around with because you had a basic issue.