I distinctly remember the very first Avengers, the giant crossover film that was built up over a series of pretty good movies (that were a reformat of previous subpar films), literally ending with Thanos staring at a shattered moon, smiling at the audience, promising/threatening there will be more.
Jack SaintI feel like I'm going crazy actually remembering 2018 and the hype around infinity war because I could swear there were two very popular MCU movies clearly establishing thanos as a kind of abusive parent archetype to nebula and gamora, who ended up being the emotional core of those avengers movies