The Marvel Cinematic Universe wants fans to think Thanos was right, and it's proving that in Avengers: Endgame, the plan continues to play a significant role in Phase 4 of the MCU.
Eternals will go back through the history of the MCU timeline. From Oscar-winning director Chloé Zhao, the film explains how an alien race arrived on Earth thousands of years ago, secretly shepherding human progress. In addition to aiding society, the Eternals arrived to protect humans from evil Deviants while refraining from interfering with other conflicts. The loaded cast includes Captain Marvel.
In the final Eternals trailer, Marvel again reminds fans about Thanos' plan. According to Ajax (Salma Hayek), when the Avengers undid Thanos' Snap, the sudden return of the population had unexpected consequences. It "provided the necessary energy for the Emergence to begin." Though it's unclear precisely what the Emergence is, the Eternals don't act like it's a good thing. "How long do we have?" Ikaris replies with concern in his voice. "Seven days," Ajax answers. With the dialogue, Marvel continues to explain that the Avengers shouldn't have reversed Thanos' Snap.
The MCU's Eternals is just the latest project to proselytize the virtue of Thanos' Snap. The Eternals trailer makes it clear that Marvel's What If...? episode 2 even turns the Snap into a gag, with a reformed Thanos explaining over and over that his plan would've been efficient. Time and time again, the MCU refuses to give up harping on the righteousness of the Snap.
Though Marvel wants to defend the Snap, the message leaves out one major issue. No matter how efficient Thanos believes his plan is or what problems emerge from the MCU's mysterious "Emergence" in Eternals, the end doesn't justify the means. Yes, killing billions allows there to be more resources. But it's still killing billions. With the snap playing such a major role in the first three phases of the MCU, it's clear Marvel doesn't want to abandon the idea anytime soon. However, as Thanos is told at the end of What If...? episode 2, his snap still sounds "an awful lot like genocide."
