Comment by repiret

You can use too few bits of color depth to get lossyness in PNG. More generally, I can't find myself very sympathetic to "I don't want a format that can do X and Y, because I might accidentally select X when I want Y in my software". You might accidentally choose JPG when you want PNG too. Or accidentally resample the image. Or delete your files.

If you want a robust lossless workflow, PNG isn't the answer. Automating the fiddly parts and validating that the automation does what you want is the answer.