Comment by croemer

Yep, I've been advocating zstd since I started working in the field. It compresses and decompresses so much faster than xz and is much much more compact than gzip. All public SARS-CoV-2 consensus sequences are ~300GB uncompressed. If you compress using gzip you end up with ~30GB. With xz/zstd you can get it down to ~2GB. However xz takes ~40min to uncompress, whereas zstd can do it in ~8min.