I am a firm believer that yes it does affect things such as communications. I have also noted that when I get readings during this period they are either delayed or inaccurate and unclear, especially tool readings.
BE CAREFUL WHEN YOU ORDER READINGS OR SPELL CASTING DURING THIS TIME
I have seen it again and again when I consult others and when I do readings for myself and others. Any info you get during that time could be misguiding, confusing or just plain inaccurate. You will simply waste your time and money or if your lucky enough, the reader will disappear and refund you.
I had ordered a couple of pendulum and card readings from 2 trusted Etsy sellers lately, forgetting that it was Mercury RX and they got nearly everything off.
With that being said, some signs are affected more than others. Those with a predominant air element in their natal charts, which symbolizes communications, are affected the most. Same goes with people with a strong Saturn in their chart e.g Saturn square mercury or an ascendant ruled by Saturn.