UPDATE 1 (7/13 PM) Don’t revoke access yet. That may be one trigger for home deletion, given first-hand experience.
I was tipped off to TiVo potentially having inappropriate access to Google accounts. Sadly, I can confirm something is amiss (as pictured above) with the TiVo Stream 4K. Beyond mere access to information, some suspect the TiVo linkage is responsible for inadvertently deleting Google devices, groups, and even Nest homes.
As of Friday, someone who identifies himself as a TiVo rep confirmed there is an issue, while placing the blame on Google and indicating that a fix is being worked. I suggest immediately delinking TiVo from your Google account until remediation has been confirmed. Which is exactly what I’ll be doing.
UPDATE 2 (7/14 AM) Revoking an Android TV device from your account will potentially wreck havoc on your Google/Nest Home experience, including device and subscription delinkage. TiVo and/or manufacturer not getting their hardware trusted resulted in an account security alert, leading some of us to revoke access, thus surfacing the Google issue. However, TiVo knew as of at least last week that something was up and didn’t warn us. But, hopefully, they can help pressure Google into making us whole.
UPDATE 3 (7/16 PM) Self-identified TiVo rep indicates the security alert is merely a cosmetic issue that Google is working to resolve. I had begun taking steps to recreate and record the issue, beginning to end, to document for Nest engineering and the community, and it appears the security alert has indeed been cleared. However, as Nest engineering seems to suggest users are responsible for deleting their homes and with seemingly limited historical data to help us recover, I’ve asked TiVo to please communicate breadth of situation to their Google contacts.
UPDATE 4 (7/27 PM) Google is finally acknowledging what we’ve said for weeks: Revoking Android TV wrecks havoc on Nest (and Google Home to a lesser extent). I’m still hoping Nest Support can provide my Protect link IDs, but it’s seeming unlikely at this point and they’re exploring another option to assist me.
(Thanks John M!)