I'm not hearing the japanese voices while reading the subtitles, I'm hearing my own voice. Also too busy reading to understand it. Cannot look away either. Voice acting in most dubs is alright.
I think live actions are different, as squid game's dub was rubbish
I want to be able to do other things while watching, or if I sit down to watch exclusively reading the subs means I don't pay as much attention to the animation. That said, if it's a show I want to watch, I don't mind subs, it's just not what I prefer. What I really dislike is subs on stuff in my language, they're distracting for no reason and just annoy me. I read a lot in school instead of having friends (unfortunately), so not a bad at reading issue.
I can watch details of a show and take in more of its meaning when I don't have to stare at the bottom of the screen and see the rest with periferials. Subtitles were likely better on TVs 32" and smaller. A 55+" TV and you really are missing a lot of the effort put into the film/animation if you are stuck having your focus shift to the bottom of the screen (not where the film makers wanted your eyes resting/darting)