While a number of people push that false meme repeatedly, everything I've heard from people who've used it (or worked on it, but the latter comes with obvious bias) is that the paid human support on GCP is good.
Heck, on the consumer side, I've gotten good (quality and speed) human support on Google Express, too.
Honestly though I can't say I've ever really needed support on GCP, most of the times I've raised tickets its been due to funny behaviour (slow spinning disks in us-central1 was the last one).
Is where you can talk to a human every time you file a ticket related to Google Cloud Platform.
(disclosure: a human that answers those tickets)
(We have support, more than 600 security engineers alone, we just offer commercial support for a commercial product.)
Source: Pay for many Google services, received support when needed.