check out My Tank Is Fight! if you haven't

so many weird weapons developed over the years

Yes but you have to account for the barely-functioning melted brain factor. Reality just can't compete when an old man goes "pew pew! zoom!"

Relevance is obviously not the Fuhrer's concern.

https://backintimetoday.com/hitlers-war-follies-the-10-blund...

A new surface vehicle for naval warfare is absolutely bonkers in the modern era. Even in the littoral space where notionally you don't have the depth for a sub-surface launcher, the LCS project was a complete bust. For anything in deep water, a submarine platform is so much more useful for projecting force and not a sitting duck.