Its on my roadmap to improve this eventually, but currently I'm focused on saving raw files to a filesystem, because it's more accessible to most users, and easier to pipe into other tools.
I encourage people to use ZFS to do deduping and compression at the filesystem layer.
The entire WARC ecosystem is kind of a mess.
Our tools do the best that we can with an old format that is in use by many institutions. The WARC format does not account for H2/H3 data, which is used by most sites nowadays.
The goal of our (Webreocrder) tools is to preserve interactive web content with as much fidelity as possible and make them accessible/viewable in the browser. That means stripping TLS, H2/H3, sometimes forcing a certain video resolution, etc.. while preserving the authenticity and interactivity of the site. It can be a tricky balance.
If the goal is to preserve 'raw bytes sent over the network' you can use Wireshark / packet capture, but your archive won't necessarily be useful to a human.