A lot of the legendary effects feel like they would have made good tier set bonuses once upon a time. X% damage to Y spell sort of thing. There are a few that somewhat alter how you play, but at least for Mage it’s not necessarily a good thing (eg: Glacial Fragments = IL spam).
Similar to the prevous 2 expansions, it’s just someone silly in a higher position playing around with new systems of borrowed power. Artefacts were OK but the legion legendary system was borked, azerite was terrible, corruption was worse, covenants are a poor idea, conduits aren’t great and there’s usually one you’ll run all expansion, new legendaries are poorly thought out and most are useless…
Be nice to have the next expansion focus on the classes and not the systems. Looking back at previous expansions that focused on making the specs work baseline (MoP and WoD) I don’t remember having a single class that wasn’t fun to play and didn’t feel good. That should be their goal. Spend less resources on developing convoluted new systems every expansion, and fix the actual specs. Maybe then, players will stick around for more than half a raid tier…