They did build some valuable tech, no question there, but be sure to account for the typical startup hyperbole. By the time you can get your hands on this (if that ever happens), the hyperbole will converge a bit closer to reality, the tradeoffs will become apparent, etc, and you'll discover that it is not, in fact, going to "smash" barriers of any kind in any practical sense.

From TFA: "Cerebras hasn’t released MLPerf results or any other independently verifiable apples-to-apples comparisons."

That's all you really need to know.