Hypersonic missiles as part of a mixed magazine

Will hypersonic missiles quickly replace Tomahawks and other conventional anti-ship missiles?

Probably not: they are large and expensive, so a few are more likely to complement a larger conventional magazine.

A new missile type does not immediately replace every older weapon. Hypersonic weapons are likely to be physically large and expensive, limiting how many a ship can carry. A few exquisite rounds can cover the hardest targets, while conventional missiles provide the volume needed for routine strikes and a sustained campaign. Guns and other weapons remain part of the same mixed magazine because no single missile solves every engagement economically.