That's exactly what I was trying to point out: I don't want to save my changes in a different format, I would like to *keep* the format of my export. Any other software I am currently using allows me to save changes in the current file format (as long as it is supported and not read-only) when you click "Save". Just with Photo this is different: I export a TIFF, open it in Photo, and Photo would not allow me to save the changes to the original file. Instead, I am asked to save my changes as ".afphoto".
Imagine you open a .docx in Word and Word would not allow you to save the changes unless you choose ".pdf" (or something else) as file format. Wouldn't that be weird?
My request would be that the "Save" functionality does what the user expects: to save the currently open file in the current format. This would immediately solve all the issues, no matter if Lightroom, Capture One, or others.