After playing so many times this meta, i think the problem is not the difficulty of the mechanics. They are easy to learn if you pay attention (In my experience, i was afraid of the wisp mechanics, but then i realized how EASY they are once you know what you have to do). The problem is how easy is for the meta to fail. (difficulty of the meta isn't the same as how easy is to be sabotaged by trolls/newbies)
This is not new. These past days I did Dragonfall meta and Dragonstorm for the legendary mats drop, and there was people who didn't want to stop attacking even when map chat was flooded with insults and nice people trying to explain them why they needed to stop. In these 2 metas, the meta could fail thanks to these trolls/newbies who didn't pay attention, but there is always enough time as back up to get them done if there's actually people who can pull their own weight.
In Dragon's End it's not that easy. You just need to be matched with a troll to make the wisp mechanics fail and affect the meta negatively. Sure, with these past nerf the meta is *still* doable if you fail them, but then you have this RNG on the boss's attacks and movements, and that makes a big difference between success with even 2 min+ left, or failing with 10%+ hp left.
What Anet needs to do is to make the wisp have a parallel timer and so that not all players turned into wisp have to get back to their bodies. For example, if 3 go, only 2 have to get back to succeed. This way, the wisp mechanics won't depend on luck and there won't be any chance for trolls to waste everyone's time. Also, maybe adding a cooldown on the boss's movement from one side to the other, so it's impossibe to spam it making everyone lose precious time. (THIS is something that also makes the meta so hard to success, and it is purely based on luck, not skill)
Oh, and I'd love to see an even harder version of this final fight if it comes as a raid/strike/fractal in a future. The problem right now is the 2 hours you need to invest every time you want to try it. Instanced content has the advantage of starting whenever you feel ready and having a previously made squad, and if you think you messed up at some point during the event, you can just reset it by writting /GG. In this open world event, you don't :')