The US 'ploughs its own furrow' with a new Infantry Rifle.

[CINDERS]

So a possible load out for a squad would be 5.56/308/6.8 - training ammo that may not shoot to the same poi less recoil then one goes into the field where its at the pointy end with the fighting ammo with its 80000 psi ammo and harsher recoil how will they perform.
Then ol mate runs out of his hot ammo who is he gunna get some off, they going to be loaded up to the gunnels with ammo isn't it prudent to at least have compatible ammunition in your group incase of an extended fire fight.
Or just equip the whole squad with the new weaponry, bean counters!

I was having a coffee with a serving SASR member a few days ago and much was the discussion on how our troops were equipped or the lack of.
SASR are a bit more fortunate than the regs but they still had to pilfer when deployed, I cannot fathom the successive govt cutbacks that have placed our country ripe for the picking we would be an easier target than the Ukraine.
And to form a militia well Johnny Howard saw to that occurrence never happening.