The delayed-choice quantum eraser experiment itself was not proven fake or invalid, but the popular claim that it rewrites the past or proves retrocausality has been thoroughly debunked.

What Was Debunked (The Retrocausality Claim)

• No Time Travel: Early sensationalized descriptions claimed a later measurement could go back in time to change whether an earlier photon acted as a wave or a particle. [1] (https://www.youtube.com/watch?v=s5yON4Gs3D0), [2] (https://www.youtube.com/watch?v=RQv5CVELG3U)
• Data Sorting Illusion: The apparent interference patterns do not magically appear on the main screen on their own. They only show up later when experimenters use the measurement results of the entangled partner photons to post-select and sort subsets of the original data. [1] (https://www.youtube.com/watch?v=sc7FlWUAnzA), [2] (https://arvinash.com/boy-was-i-wrong-how-the-delayed-choice-quantum-eraser-really-works/), [3] (https://www.facebook.com/Deepspacerevealed/videos/the-experiment-that-proved-einstein-was-wrong-quantum-eraser/1316436190581476/)
• Overall Randomness: If you look at all the raw data collected at the main screen together without sorting it by the entangled detector outcomes, you see no interference pattern at all. [1] (http://backreaction.blogspot.com/2021/10/the-delayed-choice-quantum-eraser.html), [2] (https://www.facebook.com/Deepspacerevealed/videos/the-experiment-that-proved-einstein-was-wrong-quantum-eraser/1316436190581476/)

What is Still True (The Physics)

• Real Quantum Hardware: Actual physical implementations of the Scully-Drühl delayed-choice quantum eraser—including modern demonstrations on platforms like IBM and IonQ processors—continue to confirm standard quantum mechanics. [1] (https://www.facebook.com/Deepspacerevealed/videos/the-experiment-that-proved-einstein-was-wrong-quantum-eraser/1316436190581476/)
• Complementarity: The experiment accurately demonstrates quantum entanglement and complementarity (that “which-way” information and wave interference cannot be observed simultaneously) without breaking causality. As discussed on Physics Stack Exchange, the presence of path information in the entangled system prevents interference rather than any mystical erasure of the past. [1] (https://physicsworld.com/a/the-quantum-eraser-doesnt-rewrite-the-past-it-rewrites-observers/), [2] (https://physics.stackexchange.com/questions/255127/is-my-understanding-of-the-delayed-choice-quantum-eraser-correct), [3] (https://www.facebook.com/Deepspacerevealed/videos/the-experiment-that-proved-einstein-was-wrong-quantum-eraser/1316436190581476/)