Pine tree

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.

Shot of the crown.

The diseased portion of trunk.

Spongy / friable wood debris.

Sawdust reaccumulates at the base daily.

?Borer hole.

Here's some considerations:

*The large vertical wound looks to be a result of a lightning strike.

*The spongy friable material is all-dead heartwood, decomposing in place.

*The regularly accumulating sawdust is most likely decompositional insect derived, probably ants now. It could also be the result of woodpeckers or other birds foraging for insects.

*The holes might be the result of borers or some other insect, but that is probably the least of this tree's problems.

PRESCRIPTION

Clean up the edges of the bark along the wound, trimming back dead/dry till encountering green tissue. This will be the beginning of the live callous tissue that will be trying to close this big wound.

Remove as much of the spongy and friable material as possible, again back to hard stable wood. The spongy friable stuff is just providing a home to insects and other decay organisms like fungi or bacteria.

In fact, the systemic insecticide would probably do absolutely nothing towards eliminating any of the problems that appear to be there, since none of them are occurring in live wood where the systemic insecticide might be circulated to.

Seems plausible. We picked out a bunch of the dead wood last weekend.
Should the wound be treated topically with anything?
Or just let Mother Nature do her thing?

Letting Mother Nature do her thing is generally best, but humans always want to intervene.

I can't think of anything special to apply that might even begin to assist the process. It looks like the tree has a mulch ring around it. Widening that would help a bit, and then fertilization during the appropriate season and additional moisture during drought conditions would help as a general maintenance regime.