I want to grow up and be this ship.

And because of this ship it is easy to see how expensive topside removal must be. The vessel costed some 2.5B or so. Recovering that in a few dozen decommissionings means a Hugh price. And don't forget the operational cost of a crew of a few hundred, easily adds up to a few 100k/day. Then the topside, probably full of toxic flame retardants and asbestos needs to be dealt with.

This page has a picture that shows the vessel's layout more clearly:

https://deltamarin.com/references/pioneering-spirit-pieter-s...