a) re FaaS. Of course if you have an on-prem component, someone needs to take care of it. That's why it's on-prem. But still you can separate administration of that from the developers and have the additional new feature that you as admin don't need to care which software runs in these clusters. (In reality it's never that simple since specific hardware for the task outperforms the standard hardware by more than a margin, but at least you have to worry less about getting from cool-product:v1.0 to cool-product:v2.0 as admin anymore.
b) This dream of cross cloud portability needs to die
Well, you are either a cloud provider or a software/hardware provider that is not a cloud provider. If you are the latter of course you need a way to attack the cloud providers when everybody moves to the cloud. It's a common and traditional idea.
And at least for me it also makes sense to use such a solution. I would always go for Openshift (not working for Red Hat) since they are much better at getting on-prem to work than k8s, and you have the almost same setup and interaction experience throughout all your clouds. I hope so much that they can also find a way to more seemlessly work on arm and ppc now that IBM has bought them. Then it's truly hybrid.
PS: That said I also wouldn't trust any of these quickly assembled hybrid cloud solutions from companies who are not well known for their software achievements. It's probably only the marketing aspect that's driving these efforts and IBM has already shown that they don't trust their own solution themselves even.