I ask this question as instead of getting to this information quickly I had to search for it in a more complicated manner.
So, what Simulator devices are needed to make screenshots for all resolutions that are now required to publish or update an application in the App Store?
I believe this can be helpful to a lot of developers as the error message while uploading images is not very helpful.
As of Feb 2023:
(So, for the iPads, you only need one device.)
Here's how it looks like in practice.
Have fun!