The biggest problem with these kind of movies is they have required homework. I don't think I watched half the shows these people came from. And I really don't want to. So there's no reason for me to see this film.
Marvel spent the first 20 mins of The Marvels recapping the character stories, I suspect they'll have to do the same here. They're making an effort to minimize homework, but it cuts into film time.
It doesnt "require" homework, that's a choice. If you like any of the characters go watch their previous projects. If you don't like any of the characters then you won't have to waste the time.
It's like saying i can't start reading comics because i have to start at the beginning.
Iike any other series, You can do it the hard way if that's how you choose to approach it but you can also just jump in and see if you want to go down any of the rabbit hole you know already exist
You will also be unburdened by any of those previous works and any opinions people around you have on them.
As a few have said, only one person is from a TV series and the rest are from movies.
If a movie like this is done correctly, you don’t need to have watched what came beforehand to appreciate it. Most characters in movies have pasts, we don’t get to watch everyone’s lives from when they are born to when they die.