funny you cite midas, i mean there are just 4 raid tiers and a whole addon between midas and the current raid, and to take your eden example, yes it is more optimal to give certain squares to melees and tank, ranged don't have to care about that, so ? you make it sound like running farther away is somehow easier than staying close.
Even with 4 ranged (which would be stupid for reasons like losing the 1% aswell as melee lb) you would most likely still have 2 extra people stay close to the boss, just not the melees you don't have because guess what ? its more convenient for everybody, even for a bard it is more convenient to stay closer as that raises the chance s/he will still get a preemptive heal if the healer was a second slow or whatever. also i specified my argument about not accomandating melees in that handing out 2 designated "melee" (or "stay close") spots takes no noteworthy amount of time or skill, if you really think the 5 seconds it takes people to figure out that if everyone needs to sit in his own square you should give the ones closest to the boss to the melees and tank or for melees to actually take these spots closest to the boss when the mechanic calls for it warrants melees to just be superior to everyone else than i will have to disagree.
And yes, there were times in the past were this was different, there may again come times in the future where this will be different, but what even the most "well meaning" advocates for some kind of ranged tax advertise for is basically "make melee so much stronger than everyone else that even in the absolute worst case they will still be number one" and that one is bull, no one's lost 1000 dps (or whatever the addon in questions equivalent may have been) do to having to move out of melee range for some mechanic, yet people want to give them anywhere from 500-1000 dps just because they have to stay in range, classes AND fights being different actually should favor different classes, melee should indeed not be allways worse, but theres zero reason for them to be allways better all the same