Those aren't the primary weapons of any destroyer.
And you can't escort and defend surface ships with submarines.
Change that to 'those aren't the primary weapons of any current destroyer' and you would have a valid point. While the ship will have limited capability (the original proposal was for 128 vertical launch cells but those also have to accommodate anti-ship and anti-aircraft missiles needed for local defense) to launch Tomahawks, the primary weapon systems are intended to be the two autoloading, long range 155s. My recollection is that the range is slightly in excess of 100 miles, and each gun will carry about 750 rounds, although the final numbers may be different.
And you can't escort and defend surface ships with submarines.
Point 1 - That statement is incorrect. The attack boats were an integral part of the Carrier Strike Forces during the cold war.
Point 2 - It isn't being designed as an escort vessel, it is being designed for land attack. I don't think the current design even calls for a copter for ASW.