[Nini]

I feel like accents aren't the trouble but rather a certain cadence that's imposed on announcing. Some do sound stattaco or otherwise stilted or even tonally odd but I wouldn't put that down to accent or even dialect though would put it on being too inflexible or unnatural. These announcements can be appropriate with those voices but for some reason they've been trained and/or geared towards a specific delivery style, great for a specific tone or mood but incongruous outside of it.

That can be unlearned, stiffness eased out and loosened up but I wouldn't say "oh, it's definitely these accents" because it reminds me of the exact same stuff that was said when RP was gradually phased out for less staid voices. Maybe, just maybe, a lot of this thread exists merely out of hearing a voice that makes them uncomfortable.