Because publishing a web page on any blog site lets you specify the recipients ?
To be a "protocol" imply a sort of "standard" shared , improved and used by different "actors" ( that's the reason for a protocol : two different people aggreing on a way to communicate). Twitter has always been centralized and closed in that sense.
Tweets do have recipients, which makes them different from a web page.
At the next level up from the one you describe it is very much a protocol.
Users get to decide whose tweets they follow and don't. And senders can block receivers if they want to. Twitter may have a very small something to say about that (spam, community standards) but for the most that's a free choice on the part of both the sender and the receiver.
Agreed. Twitter is in no sense a protocol. I think it became a great deal once people realized it is the only place for real time information flow, or at least that's how it's perceived among the Twitter users I know.
