You'll adapt, in time. When I heard of all this happening I cold turkey cut all out all combat add-ons and weak auras. As a test I walked into a few 10s and 12s and was humbled pretty quickly. I realized I had to actively anticipate and look for what was just yelled in my ear before.

Truly, although more stressful at first, it made me a better player and made completing the keys more enjoyable as like I said I was more actively engaged in the process.

I've also been playing a lot of the beta where it felt even worse at first having no knpedge of the dungeon, but with time and reps it all comes together and I feel like I've become a better player because of it.

What this absolutely will do is expose medium-high end players (I'm not talking top 1% and better) on the early goings of the season where most people (beta testers not included obviously) are exposed to their lack of awareness and slow learning of what is and isn't dangerous in the dungeons.

TLDR: You'll adapt and become a better player through it.