Hmm, well Fedora on its own (so no Silverblue) is very much your classic way of shipping a distro. That tends to mean that, over time, "cruft" accumulates as you upgrade your system, uninstall/reinstall packages, etc. They leave bits of themselves behind that can cause unwanted behavior.

Fedora Silverblue, that Bluefin is based on, treats the entire system layer as "immutable". Basically, it ensures consistency so that upgrades and package upgrades don't leave the system in an inconsistent state.

What Bluefin adds on top of this is a set of opinionated, pre-configured layers suited for getting particular groups of tasks done. Those layers are also immutable and tested as a whole, which makes shipping those layers at velocity easy (faster upgrades, less wonky behavior on upgrade) and easy to swap between, so you can go from gaming to developer mode without worrying about an accumulation of cruft.

Is that helpful at all? There's also this announcement blog post, which I found very helpful in understanding the value proposition.