Unable to transfer JPG photos back to iPhone 15 now

Have you considered using iCloud Photos?

If your phone is using that, there are a couple of ways that you could get at the photos on a Windows PC.

1. With the aid of iCloud for Windows (Download iCloud for Windows - Apple Support)
2. Using the iCloud Web interface (https://www.icloud.com/)

iCloud Photos is a synchronization service. So if you delete a photo anywhere – from the iPhone, from iCloud, from a synced Photos library on a Mac, or from iCloud Photos on a PC – that deletes it in every synchronized place.

But as long as you were aware of that, I think this would give you a way to transfer .JPG photos back to the iPhone. You would simply upload them to iCloud Photos from your Windows PC, and let synchronization do the rest.

You can try importing these photos into your Mac first, and then drag the photo files to the "Photos" app so that they can be imported directly. If you find that these photos are not on the correct timeline, you can use the "Details" feature in the iPad's "Photos" app to quickly adjust them to the correct timeline.

As Servant of Cats says, iCloud Photos is the way to go. Transferring pictures from phone to Mac by cable works, mostly, but transferring by cable from Mac to the phone doesn't include all the information, and lots and lots of people have had awful experiences. If you continue to do this, be sure you save all the pictures-- that's the presumption in the design of the cable transfer. Transferring them to the phone doesn't preserve them, because they do not come completely under the control of the Photos app.

On my Mac I have two Libraries. On the one that's connected to iCloud, I have only my favorites. The other is more like an archive. (Actually, I have several others.) The Favorites Library is, of course, smaller, so I can also keep my iCloud account smaller. Like you, I much prefer organizing and editing pictures on the Mac, but I like carrying around and sharing my favorite pictures on my phone and iPad. This is the way to go.

RMead wrote: … It is my understanding that if give icloud access to my photos I have to give it access to all of my photos. I do not want thousands of my photos on icloud.

I used iMazing for a while. I stopped using it and went to iCloud, instead. Also, I didn't like when they required me to buy a new license for a replacement phone. I guess now that it's a subscription thing, that's not an issue, but I don't know.

But it may be just what you want, and there is a Windows version. It's $50/year.

On the other hand, for $3 you can get 200GB iCloud for a month, do what you need, and then cancel.

Servant of Cats wrote: …You could use the iCloud Web interface, instead of iCloud for Windows. Then I believe you would need to specifically select the files you wanted to upload and add to iCloud Photos.

Good point!. That saves copying all the pictures to the PC. Of course, for the phone to connect to iCloud, all of the phone's pictures would be copied to iCloud.com where specific ones could be downloaded to the PC.

You could use the iCloud Web interface, instead of iCloud for Windows. Then I believe you would need to specifically select the files you wanted to upload and add to iCloud Photos.