Yes. This is exactly what needed to happen for Sega to resurrect the nearly 20-year old Dreamcast! OK, maybe we're jumping the gun here, but it's still a nice surprise to see Minecraft (well, a clone called Crafti) running on the retro hardware. It certainly looks like the real deal.
A fellow by the handle "gameblabla" posted the port a couple of days ago. It's based on a clone designed for a calculator, the Ti Nspire CX. I suppose the logic is if it can run on a calculator, then the Dreamcast should be able to handle it too.
What's interesting is that the game doesn't make use of the Dreamcast's dedicated 3D hardware, in this case the PowerVR GPU and is "entirely software rendered". As you'd expect, this means the performance isn't the greatest, though the creator says it "runs OK" and the video above does show this to be the case.
Somehow, I don't see it amassing as large an audience as the actual Minecraft, but it's a nice treat for those who haven't quite let go of the Dreamcast, uh, dream.