I dunno, I always kind of lumped "eaten by worms" and "rotted away" as synonymous.
I think that anything that can be saved ought to be. If you have ever been to Vicksburg and seen the Union ironclad Cairo; that was raised from the Yazoo River by Ed Bearss, you would know what I mean. The ship is virtual time machine. The knowledge gained would be huge. There are always surprises from what they think they will find.