See, this is where I think records should always be inflation-adjusted. It makes no sense to call a $ number a record if less people attended to watch the movie.
But there's always going to have been less people because movies had more advantages previously than they did now. It's why Gone with the Wind is always #1 - The movie played for decades in an era where theatres were a cheap source of heat/air conditioning. Movies now are fighting cable, streaming, and endless other sources of entertainment.
Inflation is a lazy way of saying "No, actually this movie didn't do that well." Despite all evidence, in the same way that Suicide Squad and Spider-Man: Homecoming were called flops despite being massive popular blockbusters.
Movies should be compared to one thing: the amount of money they make vs. the amount of money it cost to make them. If they happen to make a record along the way, good for them!