People can have various reasons for such look. It can be a symbol of non-conformity.
Official Rust spaces have a code of conduct that is inclusive and forbids discrimination, and this may attract people who otherwise wouldn’t feel comfortable to participate.
Yes, it's Blink without the bits that Google doesn't share (I wanted to be precise that nobody can compile actual Chrome from public sources, they can build Chromium which is almost but not quite the same)
Plus you can make certain sites always automatically open in their designated container, even if you followed a link. You can keep sites know for spying away from your logged in identity. You can have your banking and other important sites in another container for extra defense in depth.