Most people using these sites prefer the lossless codec flac anyway, which can be transcoded to anything.
MP3 320kbps and MP3 V0 is transparent to most (all?) people, so there’s not much of a reason to go with a newer codec, except for space savings.
There’s not even much of a reason to go with 320kbps, as V0 achieves the same quality with smaller files. That’s why almost nobody actually downloads MP3 320.
I personally think MP3 is there for historical reasons, as I don’t see a reason for using lossy codecs for archiving purposes. Just download flac and transcode it once or on demand on a media server for streaming.
Nintendo didn’t put legal pressure on emulator devs for decades at this point, which made devs less cautious about preserving their pseudonymity.
Now it’s too late and they can’t stop Nintendo from finding out who they are and which mistakes they did at some point over the years.
Maybe a new generation of emulator developers will be more protective of their identity, by using hosting providers like Njalla or privacy networks like i2p. The latter would limit access (as it requires i2p), which isn’t desirable for most users.