Coinbase is supposed to respond every support ticket raised right?
When was the last time you've sent them the ticket? Yes, knowing that they're one of the most popular exchange, they should address every customer's concern through their tickets.
Create a new email/ticket to them indicating your concern with the ticket # for that report you've sent them for it to be followed up.
I think even last weekend I submitted a report about this issue but no response for any of the tickets which I created after they asked me to verify KYC and contact them.
I don't think posting here would increase your chance to get noticed. Maybe try to make some noise on their Twitter, Reddit or something else, since Bitcointalk is probably not their focus atm.
I tried to address this issue on twitter when I fist encountered it on twitter as well but not enough followers on Twitter made my tweet to get buried.