Obviously, you reveal your email when you respond. However, with the changes enacted through T66795, the person who receives the email might be confused regarding "to whom" this would be revealed.
You receive an email from a wiki address (e.g. firstname.lastname@example.org) but by responding, you reveal your address to the user who requested the email to be sent, not to email@example.com. The concern was raised in T66795#2838671 and may not be a serious issue. Yet, adding a clarification is also harmless.