Here is a quote by General David Berger
“What we have to do now is transition to a lighter footprint, more expeditionary, more in support of a littoral environment,”
It is part of a broader strategy, transitioning from land battles against non-state actors, to a focus on near-peer rivals in the Indo-Pacific.
nationalinterest.org
Weight is literally one of the biggest issues, Marines will most likely get new Griffin light tanks, once they realize they will at least need some fire support in island missions.
This thread is going to be derailed so far so this is my last comment in this particular issue, this has nothing to do with weight, but retooling for a potential China fight, "China fight " here means confrontation with the PLA Navy...which is on track to displace the USN as the largest navy in the world.
To avoid the Chinese attaining sea control the US has reoriented its 3 maritime forces (USN, Marine corps and Coast Guard) to cooperate on ship killing.
WASHINGTON ̶ The U.S. Navy, Marine Corps, and Coast Guard released a new tri-Service maritime strategy today, entitled Advantage at Sea.
www.navy.mil
To do that the marine corps has decided to divest it's tank fleet (not just heavy MBT tank fleet, but any type of tanks, light/heavy). While increasing units equipped with long range precision fires like the HIMARS, LRHW, OpFires, shore based NSM etc.
Nothing from your link suggest that the US will replace its MBT to light tanks based on weight issue alone.
Lighter footprint here means lighter support/maintenance footprint, nothing to do with size of a tank. There's really nothing to gain if the US marine corps decided to go for a Griffin tank (which is a US army project to begin with) especially when it also needs an LCAC like the Abrams to go ashore.
It would be dumb for the US marine to simply switch from a 120mm gun to 105mm with no advantage in ship to shore mobility.
On the other hand when David Berger said expeditionary forces in the littorals, he means this:
Marines in Japan got a look at what the Corps' future missions could look like during a recent island-hopping naval exercise in the East China Sea.
After a small team of reconnaissance Marines landed on an island during the first-of-its-kind Exercise Noble Fury, a larger force swooped in on MV-22 Ospreys and AH-1Z Viper attack helicopters. The grunts "quickly seized control of the island, establishing defensive positions," according to a news release on the exercise.
Read Next: Fort Bragg Now Admits its Twitter Account Wasn't Hacked
The Marines then coordinated with Seventh Fleet sailors, who had identified a target they couldn't engage. After passing info along to the Marines ashore, an Air Force MC-130J Super Hercules landed on an expeditionary airfield in the middle of the night with a high-mobility artillery rocket system, or HIMARS.
"The HIMARS team fired a notional shot, destroying the target, and quickly loaded back into the MC-130J, taking off minutes after landing on the island," the release states. The Marines then loaded into CH-53E Super Stallions, it adds, and "were on the move again to prepare for follow-on missions."
The Marine Corps just stood up the first of a new kind of unit designed to battle Chinese forces in the Western Pacific.
www.google.com
So nothing to do with tanks weight, the US navy "gator navy" is big enough to haul ass. Abrams is never a problem...when you're fighting a land war. Now that Marine corps are retooled for a naval war in support of the US navy and Coast guards especially in the first and second island chain, tanks are seen as obsolete.