but what would be the blast radius for ZFS?

Most enterprises don't seem to be running ZFS with Linux, and the only large target using FreeBSD I can think of is Netflix, but AFAIR they don't use ZFS either.

Oracle sues when there's $$$ to make, but I don't think ZFS would warrant them much.

I'm not sure Larry would be interested in suing Matt Ahrens (one of the original designers), or a handful of LLNL employees (ie the US government).

It’s why I run btrfs on my lab machines. I’ve used ZFS for, looks at calendar oh, wow, literally decades now. It’s fantastic. But the miasma of Oracle’s infection keeps me from recommending it for anything commercial.

ZFS, in a vacuum is fantastic. But it’s not in a vacuum.

There's no zfs grenade. It's CDDL, feel free to use it wherever you want. Oracle can't come after you for violating the gpl even if somehow using zfs on linux violates the gpl.