Earlier quoted context omitted.
Backbones appear to be included.
Possibly, but it's much harder to intercept and mitm specific traffic at that level. On the ISP-side, that's different: they can with high certainty say that some traffic is coming from/to a specific suspect, much like a phone surveillance. This might also apply to individual service, e.g. an email provider.
Raise your hand if you use TLS between your database server and your web frontend. Keep your hand up if you rotated that certificate in the last month. Keep your hand up if you know whether your database's certificate has been tampered with. (i.e. do you check that it's signed by your internal CA? Then who is signing it? Who maintains the ca-certs package? What does the certificate verification code even look like?)
No hands up? Good! The government thanks you for your service. Keep doing what you're doing, they'll keep you safe.