Vaultwarden is not compiled from Bitwarden’s code, it’s a separate project and codebase but designed to be compatible with Bitwarden’s API.
Bitwarden is open source and you can self-host it but IIRC it’s a bit more complex and resource-hungry than Vaultwarden.
The United States abandoned the gold standard. I am guessing the point of this website is to suggest that was a bad thing. There is a lot of debate around the gold standard and most “mainstream” economists have no love for it, so I’m not saying the website is right or wrong, just that that’s what it’s about.