The ability to specify an unambiguous font for password fields, for example, makes absolute sense.

And the app defaulting to the monospace font is not an appropriate solution, because a user may pick a monospace default which isn’t unambiguous. Not every app requires unambiguity the way a password field might, so to require the user to change their default font is not a great solution.

There’s a reason emacs, vim, etc allow you to set your own fonts specific to the app that’s different from your DE defaults. That’s because they have very specific requirements that may be different from what you’re looking for in a general default font for your DE. The same is true for something like the password field of a password manager app.

Honestly, certain devs in this case started insulting the OP well before the OP said anything unreasonable, probably because for some reason they came up with the idea that the OP thought this was a heinous bug when, as they clarified, that was an invention on the reader’s part with no grounding in anything the OP said, who was not calling it a bug, nor by any means calling it heinous. Of course the discussion went off the rails after that with the OP unnecessarily getting personal, but I can see where their frustration came from even if they shouldn’t really have acted on it.