This article in the Navy times tells us that the US military is finally addressing the issues with the 5.56 mm round that has been in use for so long.
IMHO, these soldiers should have the most lethal round available to them. It’s not like they shoot someone without the intent to cause great bodily harm and/or death.
While the merits of different caliber/bullet/rifle combinations have gone on(and will go on)forever, the fact is that the 5.56 round has issues. Some of these are being addressed with the change to the new bullet design.
But there is no substitute for bullet weight and diameter. Speed helps, but only so much.
A heavy, larger caliber bullet turns cover into concealment.
But this new bullet design should help them do what they do best.
Break things and kill people.