A Zumwalt with 5 inch gun offers almost no mission capability above a simple coast guard cutter.

They're putting hypersonics on it because they've got 3 hulls and might as well get some value out of them, but not because it's what you'd design for from scratch.

The Zumwalt program was dumb from day 1. It was driven by elderly people on the congressional arms committees that have romantic notions of battleships blasting it out.

The reality is since the development of anti ship missiles, sitting off the coast and plinking at someone is suicidal, even if you have stealth shaping and uber guns of some sort.

It was a DoA mission concept.

The Zumwalt class are being refitted to carry CSP. And the boutique gun system is really a complex thing, it's not like packing in a bunch of VLS containers.