

Yet being able to uncover what they did after the fact seems hella sketchy.
Not really if you know how this kind of computing/information technology works.
A file consists of the data itself, and a pointer to the data location on the storage device or index record. When the computer wants to retrieve the data, it looks at the index to get the data location, then goes to that location to get the data. This is how the majority of computers/devices work. When a file is “deleted” the index is usually the only thing that goes away, not the data itself. Over the course of time, the data is eventually overwritten as its in areas marked as “free space”. So other new files will occupy some or all of that space changing it to hold the new file data.
If you want to get rid of the data itself, that is usually considered “purge” where the data is intentionally overwritten with something else to make the data irretrievable.
What the Google engineers were able to do was essentially go through all the areas marked as “free space” across dozens (hundreds?) of cloud servers that hold customer Nest camera data and try to find any parts that hadn’t been overwritten yet by new data. This is probably part of why it took so long to produce the video. Its like sorting through a giant dumpster to find an accidentally discarded wedding ring.

I hope its not one of the 32 TP-Link cameras that have unpatched auth flaws allowing malicious actors to reset the admin credentials in them.. This is a local exploit, so you’re probably okay, but these exploits could be used in concert with others to compromise your security/privacy.