Buy in to Kubernetes, buy in to Google Anthos, have the appearance of flexibility, but get used to GCP's tooling, quirks, documentation, etc, etc, and before long you're considering GC as the first option for all new development.
It makes perfect sense from where they are in the market.
They aren't doing anything to block us from leaving, and anyone here thinking there is going to be some kind of 100% unified API between every cloud provider is out of touch with reality, if that is what their expectation of "no vendor lock-in" is.
You can also see this in healthcare with Epic. They use absolutely bizarre names for everything to the point that it is hard for organizations using Epic to talk to organizations using other EHRs, or for employees to move between them. And since they have an absolute stranglehold on training and documentation, you basically have to go through them to be indoctrinated.
Folks have a real fear of change and learning is viewed as difficult and/or annoying. This can create considerable inertia that you can exploit.
On the other hand, where you do get potential stickiness are in the differentiated managed service offerings Google Cloud offers. These range broadly, from industry solutions & APIs to AI/ML services, to more more core data products (Spanner, Dataproc, BigQuery).
The second set of products/services don't really have any bearing on the OSS strategy and is unfair to position Google as being intentionally disingenuous in the marketing.