The linked article makes a good point.
With all due respect to Marines past and present (and I really mean that), the argument for the redundant cost of the Marines is weaker every decade. Is it time to modernize, and let the Army, and the Naval special operations teams, perform traditional Marine Corps roles? If the Pacific theater in WWII solidified the need for Marines, then D-Day (a 100% Army operation, and the largest amphibious operation in the history of the world) totally undermined that need. Large scale Marine operations are redundant to the Army, and small scale and support Marine operations could be handled by other services.
This is not an indictment of the Marine Corps. Indeed, their storied history can be retained in the Army along side storied specialized Army units like the 101st, the 82nd, etc. So, the Corps would not actually be abolished. It's reporting structure would just change, allowing it to fully leverage the support the Army can give it.
This is just a recognition of the lack of need for the cost of an independent Corps given how the nature of combat has developed over the past two centuries.
Link: https://thehill.com/opinion/national-security/5615654-the-marine-corps-just-had-its-250th-birthday-now-lets-abolish-it/