I'm absolutely no expert like some others here. But, here's my opinion. Everything we do to tires, from internal, external, fresh vs cured, cutting, and sanding is in the name of Heat management.
-Thick tire, takes longer to heat up, but maintains heat longer, and potentially reaches a higher equilibrium. Which lends it's self to as mentioned above, thick rubber is generally used on colder, softer, wetter tracks. Lower bite tracks that you want that tire to be able to move around. Generate heat and then maintain that heat as long as it was rolled and prepped correctly.
-Thin tire, takes less time to heat up, but will lose heat faster. Generally runs cooler in the long run, but should fire back just as easy, as long as it was prepped correctly.
So when the track is starting to get really hard, especially when it starts to bite up and you'd start to go towards low prep, or no prep Maxxis. If you find yourself thinking, I need an older more durable tire, the track is chewing up fresh tires. But, you see others on brand new stickers, you could be considering a thinner tire. Because, one you're wanting to keep the heat down, and not over heat that tire. If a non wiped Maxxis is "too much" and is still getting chewed up, like it most likely would at Iron City. Then cutting that tire thinner would help alleviate heat in that tire. By allowing it fire off well, but dissipate heat easier through the thinner rubber, and keep the equilibrium a tad bit lower than a full rubber tire. Now, how thin is the question. I know Iron City bites up damn good, so it's something you just have to figure out.
So when a tire wears, it's because it was heated to, or beyond it's optimal temp. So a tires dissipates heat by shedding rubber. That's why you'll almost always see tire wear progress nearly the same on any tire we use for racing.
-No change or looks slick/glazed. Not enough heat to reach equilibrium and probably perform poorly, but not always.
-Very very light graining(Fuzzed), means the tire was pretty optimal but was clearly shedding rubber to lose heat, but didn't need to really lose much heat.
-Light graining(More noticable), means it was slightly hotter than it wanted to be, it was peeling rubber off to help it lose built up heat.
-Heavy graining(Course or big grains lifted), Definitely over heated, but depending on the use it could have been perfectly fine and expected.
-Edges peeling or blistered.(Long waves of rubber laid over each other) Obviously well past it's equilibrium and clearly over heating for various reasons.
Now, the problem this all leads you down a rabbit hole too is that heat is also managed by other aspects as I mentioned above. You have internal, external, fresh tires, vs cured tires, cutting is just another tool in the arsenal. There is no right or wrong way and how you get to the end goal is up to you. This is all essentially thick vs thin for Maxxis only. This doesn't even begin to touch on profiles for cut tires, which in other brands could play almost as big a role. Which most now are only flat cutting the center of Maxxis. Not even cutting the whole tire.