Yeah uh I do not believe for a moment that Google, of all places, "forgot" to renew a security certificate for Chromecasts.
Broken automated process, maybe, if I'm being generous. But manual renewal of something like that? Absolutely no chance.
@joepie91 I recall Google posting on CA mailing lists asking about how they should do IP address certificates on their ACME CA, which are not even that common
@joepie91 (the CA is https://pki.goog/, it's publicly trusted and it's been available to google cloud users for a few years, but google was using it internally for longer)
Like, Google (security/ops) nerds try to automate anything that isn't bolted down, and some things that are.