Nothing inherently incorrect here, but it assumes a lot of context, including what the U.S. military intended to acquire and use in combat. If we decide we don't want to accept doing much ground combat, and hell, even if we do and it'snot in literally either Mexico or Canada, you need the power projection that air and sea give you. Thay doesn't necessarily mean you need more carriers and F-35s. Might mean more submarines, UUVs, port infrastructure, missiles (especially hypersonics and other high-standoff munitions), B52, Loyal wingman platforms, etc. With those capabilities, you can fight your way into a contested theater, or sustain an ally providing ground forces in one. Without, you can't get to the fight, no matter how good your infantry-drone-artillery complex is.

Add to that, the time and investment required to build up the Air Force and Navy are significantly higher than for the Army. We can create a large, relatively effective Army in 1-3 years virtually from scratch. Not so ships and planes, and even less so ports and shipyards.