2002 completely a problem with the game itself?

[Brennus]

The problem unfortunately exists on both ends.

Login server capacity is limited to a finite number of connections. When your connection attempts to reestablish client-side as noted in the doc, it creates a race condition wherein it's highly likely that someone else has already taken the slot you just created while reconnecting, which results in you then being unable to connect to the login server which is now at capacity. Every 15 minutes you essentially have to pray that there is a 'slot' available in the login server as well.

Aye, you're technically correct. But the root cause of the problem is the client voluntarily dropping the connection every 15 minutes. Eliminate that, and you don't need to attempt a new login, the server doesn't have to choose between you and a zillion other competing requests, you stay connected, waiting patiently in the queue, and will eventually get recompensed with being shown to the game, on your world server.