I have posted about this previously here, but the uninformed rage posts continue, so I'll try again:
The change in minimum focusing distance isn't a bug, a production problem or an oversight. It isn't going to be fixed. It is the result of the 12 Pro Max getting a faster lens and bigger sensor. It is how the laws of optics work. This isn't an Apple issue. When Samsung made similar improvements to their top-of-the-line phone camera, guess what happened? Same thing. So you are not going to be able to make this "a big issue" unless you can change the laws of optics. Good luck with that.
Lvl415, your observation that you have to be about an inch further from the subject to be in focus compared to previous iPhones is about right. I'd say it's more in the 1 to 2 inches further range. (Would be nice if Apple gave us that spec, but no.) To those who don't do close-up photography, this may sound like much about nothing, but having to backup by 1 to 2 inches when you're in that close makes a huge difference in how frame-filling your subject is. Yes, you can enlarge or edit the photograph, to achieve something close to the same result, but both options are loss-of-quality compromises, as is using the telephoto lens to do close-up work.
There are numerous posts about "magic fixes" that involve restarts, phone replacement, manual focus control on certain apps, blah, blah, blah. None of them work because you cannot fix or replace the laws of optics. The minimum focusing distance on the 12 Pro Max is what it is.
Lots of rage posts about "so called great camera." I understand the anger from people who do a lot of close-up photography and expected the 12 Pro Max to be at least as good, if not better, than all previous iPhones for that purpose. What they got is a camera that's actually not as good FOR THAT PURPOSE, and no warning from Apple about that. But overall, it's a far superior camera system, especially for lower light photography. The combination of faster wide lens (the "normal" lens on an iPhone), much bigger sensor and sensor-shift stabilization are all big leaps forward.
My advice: if you hate the 12 Pro Max camera, then avoid the 13 Pro Max since it appears the minimum close focus distance may get bumped a bit further out again. If the rumors are true, the camera system will get a faster lens and bigger sensor compared to the 12 Pro Max. We shall see.