[kibwen]

In practice #3 is the only one that matters. For reducing dynamism/increasing caching potential, it would be fairly easy to run a fork of the site with the more dynamic features excised (donate $1 a month to get access to dynamic features like filtering). For media transcoding, that's a textbook case of a CPU-bound operation that you could offload to an isolated Rust component for a CPU savings of 99% compared to Ruby (not an exaggeration). But the exponential nature of the network scaling will still kill you despite all this, and needs to be addressed at the protocol level ASAP.

[bscphil]

The media transcoding components aren't written in Ruby, it shells out to ffmpeg or Imagemagick.