Strictly speaking, it’s not “essential”. The FileUploader could be used instead (as mentioned in this somewhat related post). And of course, there are also plugins, but even without a plugin, there are a number of ways to handle images after they’re uploaded.
The first question is, what’s the desired UX? Should the user be able to replace an uploaded image with a different one? Should the user click on the image itself to replace it, or a separate button?
It’s also important to note (and perhaps you’re already aware) that removing an image from the DB doesn’t delete the actual image file. It’s still cluttering up and consuming valuable Bubble storage. DB fields of type file or image simply contain references to the file - basically, the URL. The Bubble dev must explicitly manage their Bubble file storage using the Delete an uploaded file workflow action.