How big are these ZFS snapshots compared to the stored data size? 1:1?

I would hope one would use an SSD for something like HomeAssistant. HDDs really shine as bulk media storage (music, pictures, video) not as storage for what would be the equivalent of running an OS on it.

It’s “powerful” in the sense that it has 48 PCI lanes and can use almost 800GB of memory (ECC included). This is just way overkill on most homelabs so the extra power draw isn’t worth it.