While I don’t disagree with you, for historical purposes I think it’s important to highlight why google started its push for 100% wire encryption everywhere all the time:

The NSA and GHCQ and basically every TLA with the ability to tap a fibre cable had figured out the gap in Google’s armour: Google’s datacenter backhaul links were unencrypted. Tap into them, and you get _everything_.

I’ve no idea whether Snowdon’s leaks were a revelation or a confirmation for google themselves; either way, it’s arguably a total breach.

When I worked at PayPal back in 2003/4, one of the things we did (and I think we were the first) was encrypt the datacenter backhaul connections. This was on top of encrypting all the traffic between machines. It added a lot of expense and overhead, but security was important enough to justify it.