So, the thing about all the definitions now is there are no prototypes (the kilogram was the last one). So Wittgenstein's observation now becomes an actual claim about how our universe works.
It feels intuitively obvious/ redundant that a prototype metre is one metre long, but a statement that light in a vacuum travels a fixed distance in one second is not so obviously redundant. It doesn't matter what colour the light is? Nope. It doesn't matter when I measure? Apparently not.