I don’t think we’re far off a “final” video codec, in the sense that jpg and mp3 and zip are effectively “final” image and sound and data codecs. Sure, there are newer codecs with higher compression foot a given quality level, but at some point it’s good enough to not bother upgrading, especially when the new version costs exponentially more for negligible gain.

…maybe THIS one will be The Final Codec… doodoodoo dooo

Re: mp3, Opus is a pretty big improvement. In my experience I've found that Opus is pretty reliably transparent at 96kbit/s, whereas LAME (which really squeezes mp3 for all it's got) needs ~130kbit/s

I think encode costs are higher (although I'm struggling to find any actual data) but in my experience this is totally negligible in practice.

Of course, don't go converting all your mp3s to Opus, but if you're running a music streaming server or whatever, Opus is pretty sweet... and probably close to "as good as it gets" until/unless we figure out some crazy new tricks.