I wasn't aware of it until now and looking at en.wikipedia.org/wiki/Zalgo_te… - I expect you are right. In NVDA 2024.3 and later, we have "Unicode normalisation" which accounts for some instances where people use mathematic symbols (which look a little like letters) AS letters in text. I'm not sure it goes so far as zalgo text though, but you never know (I haven't seen a real world example).