Fair, but since you want me to be pedantic, I will.
There is no way to directly quantify, because low, mid/medium, high, top end - these are all stringently relative terms. There is no high without something lower. There is no low without something higher. There is no mid/medium without something both higher and lower.
There are several possible rotations depending on the situation and you missed them all.
You can quantify with dps parsing actually.
At this point I think heâs so insistent on heroic being high end so he can feel better about struggling with it.
How exactly would you go about extrapolating that? Iâm genuinely curious, because either I lack a very large section of knowledge, or Iâm right and there literally is not a way to extrapolate DPS parses to quantify difficulty. You might be able to do some basic division of lowered DPS across same parties but that would still be guesswork.
You can calculate how much average damage needs to be done to bosses, ads, and shields before a hard or soft enrage timer with an approximate range for what dps needs to pull without any deaths or mistakes. This number scales with players in your raid group.
But itâs generally easier to calculate for mythics because the group number has to be 20. Itâs why youâre seeing a lot of rogues and enhancement shamans and prot warriors getting played because there were winners and losers in the current meta.
MOST specs can clear up to heroic content fine when played optimally but mythic is a lot tighter with few mistakes being made.
Just always keep in mind for mythic raids:
-You need 20 players
-The 20 players have to be on your realm only until 100 guilds clear the final boss
-Plenty of mechanics are instakill raid wipes if one mistake is made, so no disconnections can happen, and lag is a risk!
-Players need to be running weak auras that tell you how to do your rotation so they can think less while doing mechanics (which some players find unfun)
Every spec can be taken to mythic
*can be
is very different from
*will be
Admittedly, I only checked the first one through your link and the rest defaulted to all percentiles, but thereâs also max where Arcane is pulling ahead substantially.
you got your wish. frost and fire are getting boosts next patch. THIS COMING TUESDAY
Good thing each class has multiple specs. If you limit yourself to one spec then you donât have the mindset for mythic raiding.
Thatâs what you get for being a Void elf
Is this what you would call an accurate measure of difficulty?
Yeah, raw numbers do. Raw numbers do not make up the bulk of added difficulty, they just artificially raise the minimum item level and stat optimization needed for completion. It also punishes poor rotational play more, but given the parses people get in RWF, you donât need to be perfect on that, either. Thatâs not a secret, though.
I play with OCE frequently with no problem.
No one demands rotation WAs. Literally no one. Not even RWF players use them ubiquitously. Some use things to track buffs, and I do too, because I donât want to look at my buffs to see how much MSW I have, or how long is left on Barbed frenzy.
So, unless you think higher HP and higher outgoing damage is the equivalent to all difficulty, I fail to see how youâd be extrapolating accurately.
Since I keep being accused of being toxic Iâm going to actually do it.
I found out why he is pushing so hard to make heroic âhigh endâ content.
https://www.warcraftlogs.com/character/us/wyrmrest-accord/spathy#difficulty=3
I think being able to successfully pull off mechanics as a group while meeting your dps checks is an accurate enough gauge of difficulty (healers have to meet their healing quotas and be in the right positions but Iâm talking dps role here). There is nothing else to guage difficulty at all if you donât think these two things matter.
Sure, so letâs extrapolate that data through DPS parsesâŚ
Wait, thatâs not how parses work. I have two terrible parses on my two Heroic bosses so far (Iâll spare you the excuse, itâs on my record and I have to live with it until I log myself again. These things happen.)
I cleared no problem. 
You can check how much damage I took, and I definitely didnât do mechanics perfectly, either, though I did do well enough.
And for the record, I was far from the worst in taking damage on those fights, either. Iâm not sure where I fell for DPS on those pulls, I donât think I was dead last but it was not a respectable time.
Thatâs because somebody (probably multiple people) carried you by picking up the slack and overperforming in the average group dps bracket.
You failed as an individual but succeeded as a group. This gets easier to do as more loot drops for your collective group. Thatâs what âgetting a carryâ is called.
Because your group has to be good enough at communication and doing mechanics. Many groups have difficulty communicating, organizing callouts, being in the right position, doing interrupts, etc.
You also have to have the proper gear in this level to beat dps checks. This is a game that relies on stats. You can do every mechanics right and do your rotation right but simply have too low of a gear level.
Gear drops require time investments. You can get lucky with a drop, or you can spend a long time playing getting what you donât need and underperforming through little fault of your own.
This is why your groupâs (if you have one-- many people who play this game do not) communication abilities is a safety net of sorts.
They didnât. These logs are public, people did better than me, but no slack was picked up. Average parses were the norm.
But letâs assume this was the case. Why wouldnât that be feasible for the tons of people you say âcanâtâ Heroic raid?
I know you arenât talking about people being carried when youâre equal or under your tanks damage on every normal fight I looked at.
I mean I also donât use stat pots becasue $$$$ and I also enjoy learning fights at my own pace. I havnât denied being carried before in terms of dps. 
But I am often middle of the pack in my own raid group.