Still seems to hold true:

• “Second, the data will be in the clear and thus vulnerable as it passes into the target node and is fanned out to the target application”
• https://www.washingtonpost.com/world/national-security/nsa-infiltrates-links-to-yahoo-google-data-centers-worldwide-snowden-documents-say/2013/10/30/e51d661e-4166-11e3-8b74-d89d714ca4dd_story.html

An old friend used to say the end to end argument could be used to argue against IP firewalls. That does not seem to have stood the test of time. Seems like if you want reliable systems you have to both: build it watertight end-to-end, and also build layers to buttress against failure.