AWS has the first mover advantage and enormous brand penetration - it's literally the "you can't get fired for choosing AWS" (instead your company might fold due to AWS bills, but you'll be clean).
Meanwhile Google seems to be much less known in cloud infrastructure space - people think of Google Apps/Workspaces, not GCP, and they seemed to have serious problem getting to clients. I know I was quite surprised by the available stuff and low prices when I did my first project on GCP back in 2016, and generally I've been pleasantly surprised except by their horrible billing support (Google can't into actually getting paid?)
They are in this funny situation where they constantly seem to be lacking fully blown virtuous cycle of adopters and supporting companies, despite having some of the best options on the market - but I think the real issue is that they are neither the first mover (AWS) nor "canonical windows source" as with Azure.
Some of that impression is leftover from the way App Engine handled things and the first impression that left, but even GCP documentation itself still seems to struggle outside of "Google approved" languages.
Disclaimer: I interviewed with GCP as a .NET developer with a lot of experience in .NET to try to improve the situation. I got a lot of nasty ego directed at me that interviewers didn't trust my technical expertise because it was in such a "gross" stack and didn't know how to interview me technically. I personally saw that as direct evidence for why I'd never use GCP.