It’s distracting. Every time some glow is added it draws your attention to it and therefore away from something else, so adding a glow that sets your vision somewhere with duplicate information that you already know intuitively as well is just stupid.
I’m not too bothered because I hide most of my action bars anyway, but yeah I’d absolutely want to turn this tragedy off.
Blizzard has no idea how to make a good UI. It’s time for a search and replace operation, I’m tired of this.