Remove the delete/archive button from iPhone email Quite often I seem to accidentally tap the delete/archive button in the bottom left of an opened email in the iPhone email app. No matter if it's set up to delete or archive the opened mail, once you tap that button it happily removes the email without further question, no confirmation screens. Is there a way to remove that button?
That’s unfortunately part of the UI and you cannot remove the button.

Post feedback to Apple at https:/apple.com/feedback
Use a different  Mail client

I personally got tired of the limitations and idiosyncrasies of Apple’s mail and calendar applications (similar to this) and switched to Outlook.  There are many 3rd party apps; you may find one you’re more in tune with.  From what I understand, iOS/iPadOS 14 will allow you to set your own default mail, calendar and browser breaking from the built in apps.