iPhone photos no longer Import to iMac

Conba wrote: I don't understand why Apple doesn't leave well enough alone.

I can't answer that, of course, but I suspect that in making some things better, some other things inevitably pass by with unnoticed problems. Apple is certainly concentrating on the more modern and versatile method of using iCloud to synchronize Photos Libraries among devices, so the older plug-in method is getting less attention. I'm guessing, of course. You can leave feedback here:

Feedback - Photos - Apple

As to the import problem, I can't really test this, since I use iCloud, but I know that some people have found that it helps to do a forced restart of the phone.

Force restart iPhone - Apple Support

This is different from a simple Power Off. I had to continue holding the button down past the "slide to power off" message, and then I released the button only after  the Apple Logo appeared indicating a re-start. 

Similarly, it's worth it to try re-starting the Mac. If that doesn't work, then you should try to re-start the Mac in Safe Mode. This bypasses certain potentially disruptive processes, and it often helps. Safe Mode is different for different computers, so see this: 

      Start up your Mac in safe mode - Apple Support 

If safe mode works, see if it continues after going back to normal mode.

Since you're using a cable, does the Mac ask you to unlock the phone? Try this: make sure that the phone is locked before you pug it in, and wait for the Mac to ask you to unlock it.

You should also try these things to try to narrow down the problem:

• Use another library if you have one, or make a small test Library with a few pictures in it and see if the same thing happens. You can create a new Library by closing Photos and then option-clicking on the Photos icon.
• Make a new user and see if the same problem recurs with it.  This is a bit harder, because a new user can't access a different user's stuff. You would need to temporarily move your Library out of your own user's Pictuers folder up to the general "Users" folder. 

Conba wrote: …just airdrop all 300 of the pictures

Of course-- I'm glad that works as expected! But it's still curious why the link doesn't work normally, and you have to wonder what else is messed up. Maybe nothing. It's worth trying with a different User. If it works there, then something in your User account would be causing the problem (as I've seen elsewhere,) and that might cause other problems. For instance, one type of thing that corrupts a User account is 3rd party apps like "Cleaners" and "Virus checkers" that get access to the entire account. Have you used any of those?

I can confirm that importing photos still works for me in the Photos app. When the phone is locked, you will see a message that says Preparing to Import, and that will remain until you unlock your phone. You did mention that your iPhone has been updated, so is there an update for your Mac that has not been applied? I agree with Richard.Taylor to try the Force Restart option on the phone and reboot the computer.

I think they changed the link! Try entering iOS 15. But really, it should work on the 15-- you should get a power off slider (but keep holding the side button) and then, 10 seconds or so later the phone should turn off.

It worked on my 12, and it works on my 16-- should be good in between!

Conba wrote: It did not work with another user. The only program I run occasionally is Malwarebytes.

OK-- I'm all out of ideas. There's something different between you and us, and it's not any of the stuff I thought of. That maybe leaves Ventura as the culprit. You're running the most recent version, so there's not much to do except use AirDrop, I guess. It's a good thing that works!