He has a job for another 2 months then he will be an unemployed senior advisor to a former acting Sec Def, so what he says or thinks really has little impact.
That being said, his point isn't a new one nor does it hold water for very long. The Marine Corps flexed into a large ground force because that's what the US needed it do to over the last 20 years. I do agree that the Marine Corps current make up as another light infantry division doesn't make sense going forward, but the shift away from that back into something that is more flexible and able to project force from the sea onto land is already in place.
The Navy will always need the ability to project force ashore and secure a location even if only for a short time or to allow follow on forces. The Marine Corps will look different from what it did in WW2 and for the last 20 years but it won't go away, nor should it.
Texas A&M - 148 years of tradition, unimpeded by progress.