Welp, I think this all might be coming to an anti-climactic end...
After almost 45 min, I finally met with the Genius. I was sitting there working on my MBP waiting, so when he asked me my issue I showed him the pictures and videos of the 15 PM on my Mac. His reaction and body language was basically "oof, that IS a problem." I told him "it won't be visible in the daylight lighting of the Apple Store, but if you have a windowless closet back there, then run back and go nuts."
The word used by the genius to describe it was "ghosting." He said, "how long after leaving your Home Screen do the images persist?" I laughed and said "that depends on how long do you want to keep looking at the phone. What time does your shift end?"
I said "But seriously, the images never leave. I ran an HDR YouTube "screen-cleaner/scrubber" at full brightness for an hour and they were still there just as noticeable as soon as I switched to a dark mode grey screen." And as I said on the forum, there were just as visible before I left for the store.
He ran a series of diagnostics on the phone right there at the desk, seemingly looked at the results and then read some internal Knowledge-base Articles for a couple minutes(never took the phone back to look at it in the dark) and then "Yep, that's a problem. Normally what we would do for this issue is replace the screen, but since there are no parts available for the 15's yet I will order you a replacement phone."
My response to him was, "No... Normally what I would do with a problem like this on a new phone is return it and get another phone, NOT repair it." I could see him going to look at the return date/option on the account/diagnostic screen of his iPad and the "Duh/Doh" moment he had realizing the 15's still have not been out 14 days yet. That was funny to see...
He started looking at availability of any devices in the 3 stores in the state and... bupkis.
He confirmed that normal "refurbs" don't even exist nor show up in their system yet. That this would be a "new" phone. I asked if it would "be a new sellable phone in a sealed box?" and he said, it would be a new phone in a sealed box, but not the "sellable box" and "would not come with the accessories like the cable."
I asked him how long that would take and he said, "not longer than a few days. We will give you a call as soon as it comes in."
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So there we are... I can't find another iPhone 15 Pro Max of any storage size or color for purchase at any of the Apple Stores in my state. I can't find my exact phone at BestBuy, AT&T, Walmart, etc. for pickup today or tomorrow. So it looks like I won't be returning it and will be sticking with the "new" replacement phone when it arrives.
I know some folks have said that result was not the ideal outcome with how those units identified, but here I am. I won't plan on keeping my iPhone 15 Pro Max and will just trade it in for the 16 Pro whichever when that comes out. Chances are I will replace this one more time before then anyway. I had to replace my 14 Pro once, and the phones I do keep for 2 years usually qualify to get the battery or whole phone replaced too. AppleCare is my insurance after-all.
So its a "new" replacement and not a return for me.
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For those curious about the issue itself, I did try and pick the Genius' brain and experience about that. Asked him what he thought it was and if there are others that have had that issue(he also owns the phone.) He said. "I did check and this has not been an issue we are seeing at any scale with the 15 Pro's. I have not seen this issue on my phone and no one has returned one so far to this store with that issue." We went on to talk about the heating issues that neither of us had experienced. His last meaningful comment was, "This is not likely any software related issue because if it was wide-spread enough and software related, we would most likely know that by now. This type of issue on a screen so new is likely a faulty display and is clearly not operating within spec or design."
So it seems rare (which the 1 or 2 other people this thread has discovered might confirm that), but this Store and Genius certainly agreed it was outside of any allowable tolerances. Only time will tell I guess.
Thanks everyone for coming on this journey with me and commiserating a bit on something so unusual/frustrating.
Hope everyone's screen stays pretty and your titanium frosty!
Thanks for sharing your story and your (bad) experience. I would not have accepted the replacement phone. Within 14 days, you can and should be able to return your broken phone without any problems.
I would stay with your old iPhone 14, get the money back, and wait until the 15 Pro Max is available again. But that's just my opinion.
Did he say that it was the first time he heard about this issue, or did he say he would communicate this with his boss or something like this? Maybe that's a serious problem, and your case isn't the only one.
Thanks