No you can't turn them off (well you couldn't last time I played with the audio options). I don't think they are as loud or as frequent as before, if you sit on the pad inside a station you notice long pauses between announcements now but it varies.
I have a 5.1 system on the PC and the multi-source (like a real stadium) of these announcements is very apparent.
Sorry I should clarify... inside the stations, people are still chatting, it’s the main guy / gal whos gone on a coffee break!
“Welcome commander ... etc... please proceed to landing pad etc.”
I had them vanish when my Win 10 5.1 setup went back to stereo. The station announcers were coming from the front speaker and got eliminated. When I reverted back to 5.1 all was well again.
What audio hardware are you using?
A ask as his happens to me occasionally when using my wireless headphones. I've found that by switching the dongle to another USB port fixes the problem.