IIRC, the reason these old wrecks are valuable are because they are made of pre-atomic-age steel. It can be used in sensitive equipment that atomic-age metal isn’t suitable for.
From my BRAVE Browser AI:
“Pre-atomic-age steel, also known as low-background steel or pre-war steel, is any steel produced prior to the detonation of the first nuclear bombs in the 1940s and 1950s. It is primarily sourced from shipwrecks and other steel artifacts of this era, and is often used for modern particle detectors because more modern steel is contaminated with traces of nuclear fallout. Since the cessation of atmospheric nuclear testing, background radiation has decreased to very near natural levels, making special low-background steel no longer necessary for most radiation-sensitive applications, as brand-new steel now has a low enough radioactive signature that it can generally be used in such applications. Steel made before 1945 is primarily sourced from the ocean, in sunken ships from WWII, and hasn’t been recycled and mixed with newer radioactive steel.”