I never understood that. Why do it? Then you have to pay the cast of A-lister actors. GotG... Avengers... Eternals... Lot of $$$. Such a weird way to go about it. Putting the actors within the attraction instantly ages it. It puts a clock on the attraction. A clock that will no doubt be stopped when/if something happens to said actor(s) at a later date. It just doesn't make sense financially (the cost to pay them) or practically (down the road should something happen... a death, a criminal act, a bad tweet, negative press, aged out, etc) Imagineering will have to rework it like what is already being planned with RnRC. At least with Rise over in Star Wars Park™ theres' a few "outs" should they decide to drop the actors from the attraction. Not sure if the same applies to Webslingers and the GotG Coaster.
Having the Avengers cast or any Marvel cast assembled for video footage just seems like a cop-out anyway.