The AoEs being mentioned here are controlled to a degree depending on your raid composition. For example, some mechanics are given to DPS. Usually those mechanics are given to either melee DPS or range DPS. It's quite controlled and you know who is going to get it generally if you're not doing something weird. The only time this rule is broken consistently is during Mythic raiding, where knowing everything of a fight and reacting to it is standard.
The randomness for raiding is actually quite controlled outside of Mythic, depending on the encounter.
No different than when I join statics and people configure bots to tell them what to do on Discord. I don't like it. I don't like being told what to do or where to go. I use BDM for timer's and that's it. All that shouting and alerts and what not, is not a staple of raiding. It's an option to use it or not. More than half of my guild, apparently hasn't used raiding mods for the 3 years I've been raid leading our raids.
Quite an over exaggeration.
I want to not defend World of Warcraft because I hate the rut it is in now in retail but the posts I am seeing, are making it difficult not to.