More like: When an entity (including a corp like Waymo and you as a random person alike) has information (such as camera footage), then that information can be subpoenaed.
Even when you've got your own camera on your own front porch making recordings on your own hard drive using your own isolated network: There is are long-established legal processes by which you can be ordered to hand over [a subset of] those recordings.
Neither Waymo nor you, yourself, are exceptional to these processes.
Who said anything about subpoenas? Waymo says "valid legal request". When other companies say "valid legal request" it means "a police department emailed us"
Even when you've got your own camera on your own front porch making recordings on your own hard drive using your own isolated network: There is are long-established legal processes by which you can be ordered to hand over [a subset of] those recordings.
Neither Waymo nor you, yourself, are exceptional to these processes.