WellInformedYid – “Mamer Mordechai: He says the reason for this issur is because you are mevatil his kavanah. This fits well with the view of the Magen Avraham.”
So there are other things that may mevatil someone’s kavanah during the amidah. My pet peeve that disturbs my kavanah is when I’m davining shmoneh esrei and the fellow next to me davins loud enough for me to hear him, or insists on learning aloud while others are davining shmoneh esrei. They want to enhance their kavanah on the backs of others and this is assur.