We don't expect them to have years of mmo experience. We expect a person who studied MMO mechanics and strategies after being taught them for what a look at the timeline shows as being up to TWO MONTHS to learn these very basic things we all have experience learning.(this also means we learned it isn't hard to learn)
There's also the fact that the full field control thing is really not important because the answer to everything usually turns out to be sleep the monster and keep killing the current one or have a DD that can tank hold the mob. Shiroe is a red mage. How many good redmages do you think can say with a straight face that hey should stand back so that they can strategist instead of spamming enfeebles, cures,crowd control,buffs,refresh, etc? The controller role if done is also more suited to bards since they can sit back and relax (while still enfeebling)after applying a buff that lasts several hours so they're going to be less busy than sidelining a healing class.
Minori isn't completely awful but she's easy to pick on because:
Her position as a healer is usually redundant and taking up a slot for a more useful ally(they totally should have grabbed one of the higher level(from the noob camp) dps to be a 6th member after a practice run
The moment it wasn't redundant it failed spectacularly
The strategies she usually gets credit for were just the party talking to each other instead of her inventing it all
She has the role of strategist and completely neglected to use a strategy the party used barely a fight or two earlier
Her "excellence" is for a role not used by 99% of parties specifically because it's not needed (unless you're in batshit retarded group) and when used in an MMO is basically a chatbot calling out when the monster shift changes, declares timed nukes, or is close to a preset move incase you forgot to notice it on your own somehow( a notable exception to this is EVE online since humans are usually smarter than a basic AI so they require more adaptation),
They show scenes of everyone else doing something spectacular while she stands there saying "good job everyone"
The fact that looking 30 seconds into the future really isn't that hard as the second some tard joins the alliance we already forsee the wipe , various other permutations of seeing into the future that people have in MMOs (how many times have you thought I bet that monster is totally going to do the worst thing it can and kill me in 30 seconds?)
The accomplishments of other well liked characters are being cut out for more screentime for team noob( No Naogotsu running around like a space marine from warhammer40k, no nyanta aoe rampages, Marielle looks utterly useless in the anime when she essentially nonstop healed an actual army of underleveled noobs fighting the fishbutt army.{now that i think of it those other noobs were impressive.they fought stuff that was basically hnms to them}
The fact that in an MMO party with their current setup she DOES qualify as a leech makes it easy. (Who here would honestly say a pt of pre buff sch, whm, blm sam, and melee brd is a good setup or that the sch isn't redundant? That party barely even pretends tohya is the tank. they have Rudy grab aggro and freeze the monsters like he was aoe blm in mount Z pudding soloing or one shotting them in half the depicted fights)
Japanese are also way more casual about shit than we are from my experience so we unconsciously set the bar higher for average.
It gets even worse when backlash hits for people proclaiming her greatness for what amounts to standing there as everyone else is awesome in the animations.( I just had to explain that Minori actually does cast a few minutes ago)
There are legitimate reasons for not being too impressed by her.
If she wasn't getting the spotlight I don't think anyone would really care just like how almost noone is going to bitch about an imperfect setup without brd cor mage DD DD DD in the dunes/jungles.
Spoiler: show