It depends on your target audience, nowadays blizz tries to appeal to the largest part of the community aka the casuals, is this a bad thing? maybe it is, maybe it isn't, depends on your point of view, but the point is the past raiding system affected this part of the playerbase in a negative way, therefore blizz opted for this "patches seasons" where casuals can gear up and experience current content, the people screaming for the past raiding system are a vocal minority of players that pretend to be hardcore cause they raided in vanilla yet they werent at all otherwise they would've completed all of it, when most of them didnt even step foot on naxx, its actually pitiful.