Well people outside of school don't really ask ATAR, it's like once you get uni the ATAR no one cares about, so you won't really have to worry about anyone randomly asking you. I think I got asked maybe like once or twice at uni but that was only after they found out I had a scholarship so they were curious what kind of ATAR you needed for that and I had already been friends with them for a while so it wasn't like a random person I just met. If you want to tell them then that there's nothing stopping you from doing it like others have said but like I said above the ATAR is just an entry into the uni course and after that it means nothing and people are more chill about uni marks and stuff like no one really asks other people that much. I know people with 99 ATARs with 78 WAMs in uni and other people with mid 90 ATAR with 80 WAMs