I wish VLC, plex, video players in general had the ability to automatically sync subs to audio. (automatically, not manually)
We have the technology; everything we need to do this exists. It's just not done automatically, and when using slightly off-sync subs, you have to fiddle with sub timing for ages until you find the right sync. Even more so when the subtitles have different off-sync issues for the whole movie/episode.
I've used https://github.com/kaegi/alass and sometimes it works, sometimes it doesn't. It's not an easy problem to address automatically...
Video players wouldn't want that in their codebase, maybe if it was available as a C library.