no longer see the Apple lens profile as an option

I assume that is because the profile is for a JPEG while the DNG format is a raw file.

Benjamin

Yes, camera profiles are format specific. There really isn't any benefit to converting a JPEG image to DNG. That doesn't magically make it a raw image.

LR is a Non destructive editor. Even edits made to JPG images do not change the original image file. Only on Export of an image do those edits get included into the original image giving you a New File. Which you can choose to make a new file name, Add something to the original file name (making a new file) or overwrite the original file.

It's possible to write changes to JPEG files as well. You can press Ctrl (or Cmd)/S to accomplish the same thing on JPEG or TIF images that it accomplishes on DNG files. Simply highlight the images that you want the information saved, and do the keyboard stroke.

There is nothing magical about the DNG format as far as writing the information to the file. Lightroom can do the same for original raw images by creating XMP files. And Lightroom can do the same for JPEG and other non-raw file formats. There is an option to automatically write changes to XMP that will affect not only raw images but other file formats as well. If that option is not selected, and you don't use the keyboard shortcut, then the DNG file doesn't have any changes applied to it either.

I seldom if ever use the write metadata changes to the file. I rely on the catalog to retain those changes and export copies when needed.