If you wish to prove me wrong, fix your website.
https://www.xigmanas.com/index.php?id=3 said:
ZFS v5000 (Feature Flags)
The excerpt above is absolutely meaningless. It could be anything from "LZ4 compression and large blocks" to all current ones. I know that it's most likely everything in the version of FreeBSD on which the release is based, but I sure as hell don't know that from the marketing blurb. It sounds like something thrown in there with little knowledge of the subject to pad out a features list.
In my view, you have two options here: Either specify that the latest feature flags supported in FreeBSD are supported, with a supporting link; or just say OpenZFS and keep vague, leading people to just assume you're tracking FreeBSD. But "ZFS v5000 (Feature Flags)" just screams "we have no idea what we're talking about!"