How ethical is it to build and test a submarine at a depth deeper than it’s meant to go?

Bit of an odd question, but lemme explain. I’ve been watching a few videos about submarines, and it got me wondering about a safer way to test a submarine/submersible. One way I thought of was by building a submersible to withstand depths and pressures far deeper than where it’s supposed to go.

Let’s say for instance you want to visit the Titanic (Why? No reason. No reason at all.), you could build your submarine to withstand the pressure of the Challenger Deep, and test it by dropping it down the Marianas Trench. Of course, if it can survive a dive in the Marianas Trench, then diving half that distance to see the Titanic shouldn’t be an issue right?

Would that be ethical or no?