Disagree on the point about Whedon but also I’d put BP ahead of infinity war. Infinity war, as dope as it is, is all third act shyt. As a film it only works if you’ve seen every other movie and can’t be seen in a vacuum like Black panther can be. Also black panther having something to say and not fumbling its message puts it over the top for me.
I don't know if I totally agree on that point, it's a pretty common thing people bring up about the inherent built-in fault of a movie like IW but I've known some people who haven't seen every other movie / someone who didn't see any prior Marvel movies at all and they still found a lot of enjoyment. The movie does a lot to provide detailed yet concise exposition as well as smart storytelling that builds on old threads where any viewer can deduce what's going on, where the characters are at regarding the current points of their arcs, and why things logically make sense going forward. For example, you can tell without having seen Homecoming / Civil War that Tony is a father figure mentor to Peter who disapproves of his impulsively headstrong nature, therefore the impact of Peter dying in his arms is felt. You can skip the entirety of Ragnarok and know what happened in that movie because Thor literally explains it all to the Guardians and Rocket. It's not perfect obviously but IW did such a good job of doing its best to make it a standalone movie.
What brings BP down a notch for me below IW is that it still has the deep smell of a formula. In particular, the way that it's structured and the 3rd and 2nd act tropes. I also didn't get a great feel for any dynamic shift in T'Challa's character from the start to the end. His character didn't really change because he was altruistic, kind-hearted, and open to change from the beginning of the movie. He was already kind of a perfect protagonist, just a little naive. IW, on the other hand, was totally innovative in its creative decisions and how by the end of the movie, it had brought characters to what you would consider midpoints of their arcs rather than conclusions.
I still think BP is top 3 Marvel, but I just think IW might have been as close to flawless as you can get