The Chart documents whether the carbine listed has the milspec features required by the government and specified, item by item. That's all it does.
Whether a buyer NEEDS a milspec feature, or if the milspec is even the BETTER type out there is open to discussion.
Chrome lined barrels were spec'd in 1968 as a method to reduce corrosion, principally for full auto fire, and the majority of that actually erodes the throat just forward of the case mouth. That area is critical for accuracy. To chrome a barrel, it has to be rifled oversized and plated back, which can and does affect accuracy, too. Milspec chrome barrels shoot 2MOA on the average. Precision shooters use stainless, and avoid chrome like the plague.
Another item is Magnetic Particle Inspection, which discovers if the bolt has cracks or flaws. Milspec is every bolt gets tested, civilian, maybe five out of a hundred, and the batch approved. Obviously one might slip through, Customer Service was invented as it was cheaper than testing every single item. Some prefer the Superbolts in stronger alloy, and for all the marketing, I've yet to see them claim MPI testing was done on every one. Maybe I missed it.
The point is, for all the items on the chart, it's an institution's checklist, and not guaranteed the leading edge. Nitriding the barrel is now very common, hammerforging is poised to take over when the machines get paid. Very likely in the near future, milspec might get changed to Nitride Hammerforged - like most European makers have been doing for a long time. Almost all pistol barrels are hammerforged, and quite a few civilian sporting rifles. It's the ancient milspec that requires button rifling, and it's arguably old tech and needs to go away.
Don't let the RRA bashers dump because it doesn't have a check on the chart, look into it and see if it's even necessary for you. They haven't got the lock on technology, the effort most of the time is to forewarn against the cheaper guns that can and do have failure prone parts - if they are used like combat carbines with high round counts through them.