> This is a MySQL limitation that they have fixed in recent releases (as the OP notes)
TFA notes that this is not fixed, the `utf-8` mysql encoding still isn't utf-8. And as TFA also notes related technologies (aka drivers) may not be compatible with it (the example he uses, mysql2 for Ruby, still hasn't had an official release supporting utf8mb4[0])
> it's true that Unicode is (relatively speaking) very new for such a fundamental technology
That's becoming quite hard an argument to swallow when encountering astral planes issues in 2012 when Unicode 2.0 was introduced in 1996.