

it’s my understanding that on disk compression is different from networked compression, usually networked compression uses Gzip iirc, where as on disk tends to use something like LZ, file downloads are generally less important than a file system, so you can trivially get away with costly and expensive compression.
the server isn’t live compressing it, it’s pre compressed binaries being shipped hundreds of thousands of times over, in most cases. Compression is primarily to minimize bandwidth (and also speed up downloads, since the network speed is usually the bottleneck) you can either cache the compressed files, or do a gated download, based on decompression speed.
Usually, most disks are faster than any network connection available, so it’s pretty hard to hit that bottleneck these days. HDDs included, unless you’re using SMR drives in a specific use case, and definitely not an SSD ever.
Although on the FS side, you would optimize for minimum latency, latency really fucks up a file system, that and corrupt data, so if you can ensure a minimal latency impact, as well as a reliable compression/decompression algorithm, you can get a decent trade off of some size optimization, for a bit of latency, and CPU time.
Whether or not fs based compression is good, i’m not quite sure yet, i’m bigger on de-duplication personally.