I've watched many dubbed movies and tv shows and the slightly-off lip movement never bothered me, you stop noticing it after a bit. It wouldn't be that big of an improvement.
I prefer the subs tho mainly because the voice acting in different languages is usually not great - movies’ original languages usually sound much more natural.
Think of the impact of this on dubbing movies between languages. This seems like an incredible tool.
Of course, we can’t just forget about deepfakes and such, but this particular usecase kind of excites me.