Is this not the case for GCP? I recently switched to a company running on GCP and I don't have tons of exposure to our infra, but from what I've seen, GCP reps are VERY hands-on. Even in my non-infra role, I've been exposed to several different instances of them being hands on: in setting us up, in discussing our resource needs (we're a very heavy GPU compute customer), in tracking down issues (even when the problem is likely on our end).
I don't actually know - I haven't used it myself. I've read a few comments in various places suggesting that GCP support is as nonexistent as the support for other Google services. I think somebody said they were hosting their whole company's data and services on GCP, and their entire company's account was killed because supposedly some malicious activity was detected. No details of what the activity was or why it was thought to be malicious, just poof, all of your servers and data gone, and nobody you can talk to about it.
It's possible that was misleading or they've improved since then, I don't know. Your claim that they do have quality support for corporate accounts is an interesting point on the other side though.
Yea I wouldn't take my experience as too dispositive: I gather that my relatively small company punches significantly above their weight in terms of compute needs, and I only have relatively tangential exposure to our interactions with GCP. It's just that those tangential data points have all happened to point in the direction of robust and responsive support.
