As someone in the midst of transitioning an organization to GKE, Google Domains was the first shutdown that truly frightened me - AFAIK the first true B2B IT offering that was unceremoniously shuttered. Domain registration may be a regulatory/reputational minefield - but then so are many of their other cloud offerings, up to and including content distribution. I don't think it's indicative of a larger pattern of shutting down Google Cloud services yet, but it's certainly a yellow flag at least.