Supporting caching doesn't necessarily mean intermediates can modify the requests/responses mid-air. You can still hash and sign content, and servers can cache

Supporting caching doesn't necessarily mean intermediates can modify the requests/responses mid-air. You can still hash and sign content, and servers can cache these responses. Nonetheless, that approach seems to be a way of the past. HTTPS is essentially expected now, so CDNs are required to achieve similar performance - Great news for CDNs ;)