While part of me thinks this is bad because, “it’ll make skill less relevant, they’re making it too easy,” I actually think this is a good thing overall. We had this for a while with macros, and taking pressure away from rotations has been one of my desires for a long time.
I don't think this thing will get to an insane point. It might be good enough to clear normal, but the bar to clear normal in this game hasn't been high ever since it became a difficulty setting. I think it'll handle at most the very basics and interact with procs and stuff but for the most part it isn't like beating this button is going to give you purple parses and that's even without the inherent added gcd timer taking into account which would lower it further. I see this being supremely simple minded and being like "It'll cast these debuffs if they aren't on the target already. Then it will use your main ability, dump extra resources like Astral Power when it has enough and cooldowns when they are up." I highly doubt this is going to have the thinking of like hoarding resources before a burst cycle then just dumping out perfect ability usage. Especially since it won't be able to automatically know what's going on in the fight. It might pop cooldowns and the boss goes immune, and that's a natural pitfall of using something like that that'll keep it in line and like I said, good enough to clear normal, maybe a bit of heroic and all of heroic when a raid is geared enough, but I definitely don't see it being good enough that you can get away with it in Mythic play and it not look like you dropped 30 ilvls overnight.
It'll basically be a form of training wheels for people who genuinely don't want to play the game but want to be able to do some barebones content, like normal PvE without feeling iced out of a spec or class they want to play because it is too difficult or doesn't click with them. I can think of a lot of Arcane memes from Dragonflight just off the top of my head about how Fire and Frost had to understand very little while Arcane was: "Burn phase, conserve phase, mini burn phase, etc" This isn't a hassle to anybody who expects to play their class or do heroic. It's par for the course, albeit funnily I remember being 10 and even using Cosmos UI or looking up quest locations was considered "cheating." Hell, in OSRS the developers used to make jokes about you clearly reading a quest guide and the creator of the game notoriously HATED people who looked up solutions to puzzles.
I probably won't get any use from this feature as I can stubbornly force myself to play something until it clicks, but I can definitely see the positives for the casual audience this would be aimed at. Even I've thought to myself "Oh hey, I'd really like to have this class for a character, plus it would be great for RPing" then when I look into playing it and lose all interest there. Hunter was that way where I had a lot of enthusiasm to level one and a great RP concept in mind for them then I learned I actually really despise Marksman as a playstyle in PvE so they're a BM in everything except PvP just because it's one of those specs you put in next to no effort to play and get insane results in return.
Not gonna lie though, even if this feature is largely useless and only has the benefit of more people queue dungeon finder stuff because they feel that magic button allows them to do this content (despite they can probably do this content if they wanted to) and it gets them in there and enjoying the game whilst making it feel more lively, more power to them.
When it gets to be something like WrathCombo in XIV which is essentially "Imagine if Hekili came with a button that you could spam and it casted whatever it was suggesting to you" then I might be concerned. God knows that plugin alone has killed PvE for me over there and there's no way WoW's team isn't keenly aware of XIV's plugin situation and going to watch this like hawks.