Slow yes, but bots are very patient. That would slow down innovation in the third-party ecosystem that surrounds Steem. And, speaking in general terms about cryptocurrencies, you want to encourage third-party innovation as much as possible. Such registrations become unwieldy and quite unenforceable because Steeminc becomes a bottle neck for the issuing and enforcement of those keys. It's also another centralisation step that might be a step too far for the decentralisation absolutists among us.