I did a bit of a read, apparently the 2 most popular screen reading software sources (jaws and nvda) fully support the thorn character both isolated and in words correctly as of a 2024 review, but it was a major problem in 2022, prompting improvements in recognition.

Oddly, periods at the end of a post are currently considered a larger problem as depending on site syntax the reader has problems with if it should state the existence of a period or not. (something about if there is follow up or classifying it as isolated punctuation that holds unique meaning)