I recommend having a look at mpv. It plays files, supports all the container formats and codecs you are likely to come across both for audio and video.

I sometimes reach for VLC still, but mpv is and has been my go to player for most casual video playback for years now.

The UI pretty much consists of video playback plus an auto-hiding timeline overlay. On the timeline overlay you can also select which subtitle to show as well as turn subtitles on/off.

You can install it on macOS with

  brew cask install mpv

assuming you have Homebrew installed