While an individual fact can't be copyrighted, a collection of facts does have database right protections in the EU & UK: https://en.wikipedia.org/wiki/Database_right

Yes that's true, but copyright is not the only restriction about the use of data you find online. There's trademark and privacy to consider. I don't think either thing is likely to apply to dead people :)

Trademark also doesn’t apply to facts. And if data is published on the open internet then privacy is most likely not an issue. The genealogy is already published in the open.

So I don’t think those elements are relevant to the conversation without more context.

I think this is the key point that lots of people need to understand.

Your photo of a headstone? You own the copyright.

Grandfather died on 9 June 1938 & is buried at X? Not copyrightable.