Japanese Scientists Develop Artificial Blood Compatible with All Blood Types

They said this has been ten years down the road for thirty years but I guess it's actually time if it's only five years away now.

I get why the artificial blood thing is really cool and definitely headline worthy, but why is the “compatible with all blood types” headline worthy? Wouldn’t making it incompatible involve developing additional parts to the mix, and thus be harder?

Wait, I've seen this one before.