There was a controversy when Go came out about the naming due to another language also being called Go, and the top voted alternative name was Plan9, and as an homage they may have used that internally instead.
A coating for projectiles to be able to withstand the heat from laser weapons would be one with possibly significant impact, given recent announcements.
Was about to say this. Kudos to them for actually conveying the information! They seem to have learned that what they're (partially) in the business of selling is long term trust.