You know, that's a legitimate fear, and one that both DC and Marvel are guilty of doing. Sometimes it feels like a cashgrab move to reel the readers in to buy more comics, but in recent years, there is a more concerted effort to minimize that sort of thing. Marvel introduced the Point One initiative, where you can read any comic and feel as if you're reading a complete story without needing to buy other comics. DC rebooted their whole line with The Flashpoint Paradox and the New 52 to consolidate decades of stories but was met with mixed reception so they introduced the DC Rebirth which included more self contained stories.
The events could be read by anyone picking it up for the first time, but there's just more incentive for the people who have read the other stories beforehand. More easter eggs, more payoff, that sort of thing. But, the main story could be understood even by first time readers. I guess it goes the same way for the solo movies.
So basically gone full circle as to begin with the comics were things that while there ight have been a story arc spanning a few comics you could still pick up any comic without needing to know a million years worth of backstory first? :D
Exactly! Hahaha! We always go the convoluted route after all haha! It's best route to take!