The ability to export data from GCP to maybe your own datacenter is really missing.
The aws way of doing this is nice: You rent the appliance like when importing data to the cloud and pay a (reduced) "bandwidth" fee for exporting the data to the appliance which will be shipped to you.
Another idea would be for GCP to handle export to a physical device and that device would be shipped to a known location (to both GCP and the client) and accessible by either but offline and cold stored. And similar to how paper records are stored you could put in a request to access the records and thereby verify their existence (which you can't do with cloud data other than the copy that you are able to access).
Fwiw, Iron Mountain lost about 60 physical records file boxes that we had ..
It likely wouldn't be very expensive to get a very high-capacity fiber connection going between GC/AWS datacenters in relative physical proximity.
Not expressing a particular/immediate personal need here, just noting that this could help keep the lock-in factor down and level of competition up.