How to disable inline attachment previews on viewing emails in Mail.app
There is a similar question https://discussions.apple.com/thread/252108838 but it clearly looks like the person whose answer is marked "Apple recommended" did not understand the question and therefore did not actually answer it.
In the answer, they talk about how a recipient will see a mail with attachments sent from Mail.app on their end. While the question is actually about viewing emails in Mail.app itself, regardless of who and how sent them. In fact, it's Mail.app that turns attachments either into icons or into inline previews when viewing emails in mailboxes or in their folders (regardless of how they were sent and which folder they are in: Incoming, Sent or anything else).
Currently, it is possible to force displaying all attachments as icons only when composing a new email in Mail.app (either from the context menu of an attachment, or with `defaults write com.apple.mail DisableInlineAttachmentViewing -boolean yes`.
However, when **viewing** emails (regardless of a mailbox or folder), Mail.app will always show single-page attachments as previews and multi-page attachments as icons.
So the question is: how to change the latter? How to make Mail.app always show all attachments as icons when clicking or opening existing emails for viewing?
iMac 27″, macOS 12.0