Endgame comes out on DVD on August 13. Too many people are saying that they will just wait and get it on DVD at this point. At this point it's Kevin Feige vs. the Disney process. You better believe that Feige wants Endgame to take the record, but the movie industry is at the point where the DVD/Blu-Ray comes out just a few months after the theatrical release.
Kind of sucks. In this environment a movie has to be extremely front loaded in order to take the record.
That's the evolution of media nowadays. It's easier to get content and it's easier just to wait for content just to save money and what not. Not to mention that ticket prices are not what they used to be back in the day.
Here's the Annual U.S. ticket prices over the years: https://www.natoonline.org/data/ticket-price/
Hell, the theaters I've gone to nowadays have ticket prices of $12-14, unless there are certain events going on (i.e., Tuesday Matinee or Movies Night special or something similar to that). But then again, DVDs/Blu-Rays are not necessarily cheap options either.
To be fair, it appears that its easier to be close to $500 million at the box office than it has ever been in the past for blockbusters. Hell, the majority of films in the $1 billion box office club released in the 2000s-2010s (exceptions are Titanic (1997), Star Wars Episode I - The Phantom Menace (1999), and Jurassic Park, after the 3D release (1993)). Though it would be neglectful to forget that movie budgets and marketing for big blockbuster movies are bigger nowadays. Plus, we have social media to help spread word of mouth better than ever.
The stars would have to align again for a blockbuster movie to reach the heights of Avatar, Star Wars: The Force Awakens, Avengers: Endgame, and even Titanic. All of these movies had a lot going for them to reach $2 billion. Avatar released at a time when 3D movies were trendy, James Cameron was well-regarded as a director (even to this day, I would presume), the movie released against soft competition, and the movie was well-received (82% on RT). Avengers Endgame released as a culmination of 11-years (and 20+ films) of development within the well-received MCU (so you already have a huge fanbase), a highly anticipated follow-up to another $2 billion box office member in Infinity War (as shown throughout social media), a familiar and well-regarded ensemble cast, and huge marketing. Star Wars Episode VII released 10 years since the last live action Star Wars movie (Revenge of the Sith), was well-received, and had long-time fan favorite characters returning (Han Solo, Chewbacca, C3PO, R2-D2, Leia, and, in the ending scene, Luke Skywalker). Titanic, against all odds, succeed in the box office due to great reception (89% on RT), popular rising stars (Leonardo DiCaprio and Kate Winslet) leading in a love story based on a historical event, and the awe of the film's special effects, especially in relation to the Titanic itself.