Seriously. I get tired of this "increasing complexity" shit. Are you really that far into denial? Reality check. Raiders got worse, not raids harder. Raiding is as easy as it has ever been. I would actually say it is easier now than before.
Please tell me which fight is that incredibly complex that it is miles beyond fights in previous expansions.
Which fight has suffered from this armsrace between devs pushing their raiders?
Lei-Shen N was a complete joke in comparison to other end bosses like Nefarian 10N, Cho'Gall 10N, LK10N, Yogg'Saron 10N.