It has a lot of nice autocomplete features and handles functions much better than bash. It has a very sensible autoconfig so you can just install and try it.
Zsh can be configured in quite a lot of ways. It's default config is quite similar to bash.
No, DisplayPort, DVI-D and HDMI use fundamentally the same protocol, HDMI just adds DRM which requires active adapters when one plugs in a HDMI source into a DisplayPort sink. DisplayPort to HDMI conversions are completely lossless and don't add latency AFAIK.
Some clips of DS9 exist in at least 1080p because of a documentary that scanned in the film, so Paramount could definetely do it with some of the Oracle blood money.
Autocompletions in fish also take history into account, which saves you a lot of typing in the long run.
Fish shell script is much more sensibly constructed than bash so it's just much easier to write a script in fish.