Avengers: Endgame shows why the MCU audience is well aware of Thanos’ identity:
Avengers: Endgame subtly reveals why the MCU audience knows who Thanos (Josh Brolin) is and why he snapped half the life in the universe. The Infinity Saga may have concluded, but the events of its concluding films continue to influence the Marvel Cinematic Universe’s contemporary storyline. This covers the Mad Titan’s intentions for indiscriminate extermination. However, MCU Phase 4 demonstrates that restoring the decimation has drawbacks. The Falcon and the Winter Soldier showed how a sudden flood of people forced nations to scrabble for resources while survivors of the Blip were displaced. Following that, Eternals suggested Thanos did nothing wrong after his snap rescued mankind from a larger disaster in the Emergence. This leads to Hawkeye now completely adopting the argument, stating that there are those who believe the Mad Titan was correct in severing half of the galaxy’s inhabitants in order to preserve the cosmos. It’s an intriguing concept to explore further in MCU Phase 4, especially now that the franchise has moved on from the Infinity Saga. However, some are curious how the public knows about Thanos and his motivations given that the Avengers’ battle with the villain took place in private settings such as Titan and Wakanda. Marvel Studios, on the other hand, has highlighted how citizens are fully aware of Thanos and his objectives.
Following the snap in Avengers: Infinity War, the heroes split off and spent the next five years in diverse ways:
Following the events of Avengers: Infinity War, the heroes go their own ways and spend the next five years in diverse ways. Captain America (Chris Evans) resolves to keep assisting people by conducting group therapy sessions for individuals who are still dealing with the Blip. In a short Avengers: Endgame sequence when he speaks with many guests, he pushes them to go ahead in the aftermath of the tragedy, arguing that if they didn’t, Thanos should have just murdered them as well. Based on this exchange, it appears that everyone in the room is well aware of what the Mad Titan accomplished. Most likely, Steve chose to offer his first-hand expertise in combating the enemy in order to help the public comprehend what transpired.
The Avengers felt impelled to inform the United Nations about what caused the mass disappearance of citizens:
Given the suddenness of the devastation, it’s fair to believe the Avengers felt forced to inform the UN about what caused the mass disappearance of individuals. When Avengers: Endgame opens up after the events of Avengers: Infinity War, it has already been a few weeks since the snap, and all of the remaining heroes have returned to Avengers HQ in upstate New York. Because of the time leap, spectators don’t know what happened immediately following Thanos’ snap. There’s no indication of how the Avengers departed Wakanda or why Vision’s (Paul Bettany) corpse wound up with S.W.O.R.D. rather than in their care, as seen in WandaVision. At this time, Marvel Studios has made no indication that it intends to revisit this era in the MCU’s history—especially now that the series is focusing on Phase 4 and beyond. This is not to say that it will not happen in the future. Marvel Studios’ Disney+ series allows them to handle smaller tales that might fill in the historical gaps, like offering additional background on how Thanos’ details arose.
People in the Marvel Cinematic Universe are well aware of Thanos’s deed and how the Avengers saved everyone:
For the time being, it’s apparent that the in-universe public is aware of his attack and subsequent victory. The character Monica Rambeau, played by Teyonah Parris, who was also extinguished in WandaVision, recalls particular aspects of Captain Marvel’s (Brie Larson) and Scarlet Witch’s (Elizabeth Olsen) clashes with the Mad Titan in Avengers: Endgame. As a result, it should come as no surprise that individuals have an opinion on the entire MCU tragedy.