> 99 times out 100, you want to do the same things with the image data: adjust it in some way, and save it to object storage or something.

That's kind of a bonkers expectation for the browser to fill. It's like expecting that <input type="audio" /> should let me crop the audio and add reverb to it. That's two specific manipulations out of untold thousands, and squarely within the purview of a different app. https://editor.audio/ (never used this, just an example)