Welcome, Boarderofvaldisere, to Apple Support Communities!
First, Apple doesn’t «monitor» these fora. We are just users, like yourself.
The thing is that, in all cases, all associated email files are being sent «as attachment[s]», as anyone can verify by performing the definitive test found at https://discussions.apple.com/thread/251807601?answerId=254806789022#254806789022.
Don’t believe me.
Check for yourself.
However, only a single email client (and its derivatives) has any problem allowing its users to properly perform bulk attachment operations (such as bulk-saves) upon any given received email, based upon some internal criteria known only by its creators.
No one else have such troubles, since all images (and other sent files) are provided «as attachment[s]».
Run the definitive test and see for yourself.
So. Unless and until the creator of that single email client (and its derivatives) corrects its behavior, there will be no actual fix.
Since Apple has no control over that single email client (and its derivatives), Apple can do nothing to actually fix the issue. (At best, they could find fragile workarounds for the issue. Fragile, because such workarounds are easily broken by any tiny changes in the web of interactions involved in transferring emails. This fragility was the cause of this breaking when iOS changed from 13 to 14, as well as many other times this issue occurred previously, through the years.)
(That single email client [and its derivatives] has been neglected by its creator for over a decade, now.)