How do I completely disable HTML5 Video playback on Safari?
My prev attempt at fixing this with AdGuard failed miserably. However, I just found an option in-built in Safari that solves my problem.
My initial frustrations were relating to HTML5 videos, mainly relating to the fact that they continue to auto-play even when Safari was set to not let them. And so I figured let's just disable them altogether. But maybe that was too extreme of an option. This one is a lot better!
The solution

Enable Safari Debug Menu

Run this in a Terminal window. To disable the menu replace the 1 with a 0
defaults write com.apple.Safari IncludeInternalDebugMenu 1

Restart Safari

Open the Debug Menu, and head over to Media Flags

Enable the Video Needs User Action &amp; Audio Needs User Action

Restart Safari

Now laugh at the puny websites trying their futile attempts to auto-play videos BWAHAHAHAHAHAHAHAHAHA


PS: If you are a reddit user, you might just wanna head over to their website and just try it out with these options enabled
Tested on Safari Version 14.0.2 (16610.3.7.1.9)