I use subtitles all the time, as I’m getting hard of hearing. Starting the process of getting hearing aids, whether I like it or not. Have avoided them so far – too fiddly, and “I can manage.” Geriatrician pointed out that poor hearing is the first step on the road to dementia. So, reluctantly, I’m doing it. As to needing subtitles for Aussie accents, no, never needed them for that.