Searching for a Netflix IPA for iOS 5.1.1 leads to a graveyard of broken links (RapidShare, MegaUpload) and questionable forums. Here is what exists:
Even if you successfully jailbreak and sideload an old Netflix IPA, you will face the DRM and TLS issues mentioned above. There is no "magic tweak" to fix 13 years of protocol evolution. netflix ipa ios 511
A grid of movie posters. Breaking Bad . The Office . House of Cards . Searching for a Netflix IPA for iOS 5
Netflix stopped supporting iOS 5.1.1 around 2014-2015. The last compatible app version was something like Netflix 5.0 or earlier. Today, the Netflix API (the backend service your app talks to) requires modern security protocols (TLS 1.2/1.3) that iOS 5 simply doesn’t have. A grid of movie posters
: You’re greeted with the classic "skeuomorphic" design—lots of glossy buttons and heavy textures that match the iOS 5 aesthetic. It is surprisingly snappy on an iPad 1 or iPhone 4, provided the hardware isn't bogged down by modern background processes.
This is the safest and most reliable method. It forces the App Store to offer you an older version without needing to hunt for risky external files.