Trees, Shrubs and Conifers: Pine tree, 0 by Weerobin

Weerobin wrote:
I was visiting my BIL in Hampton, Va.
He has a huge pine, one side of which has a large caved-out section.
The exposed wood is spongy and friable.
Sawdust at the base of the tree reaccumulates daily.
There are small borer holes noticeable also.
But surely this big cavity isn't caused by borers?
I really know little about the situation.
I thought maybe one of the systemic insecticides might help.
Is it a goner? Any suggestions would be appreciated.

First 2 pix are just to give you an idea of how big it is.