Display order keeps getting automatically rearranged when connected to a dual 4k monitor setup to my MBP 2019.

There are software add-ons that can read out the EDID strings involved and prove that they are the issue. The most well respected at this Is probably SwichResX.

There are no known work-around on the Mac, because the Mac relies on this data to uniquely identify displays and their names and capabilities.

If the Samsung forums is anything like the Apple forums, no problems reported there are likely to result in any Engineering Investigations. Only a Bug report filed at the end of "jumping through ALL the hoops" as you describe is likely to induce any action.

Hello bnimit,

Thank you for getting back to us.

To check to see if the issue is account specific, test the issue in another account. If you don't have another account set up, here's how to create one: Set up users, guests, and groups on Mac - Apple Support

Let us know the result.

Take care.

Hi bnimit,

To clarify what you're encountering, do you mean that the additional display isn't arrange where you expect to be in relation to the primary display, or that applications and windows, don't open on the the display you expect them to?

If the latter is the case, right click the icon for the app from the Dock, than choose Options, and select the your preferred display arrangement to set it as a default.

Let us know whether that helps.

bnimit,

Our last steps would be to ensure your MacBook Pro is updated to the latest version of macOS. This will guide you: Update macOS on Mac

If you're running the latest version, try restarting your Mac too as shown here: Shut down or restart your Mac

These may help to resolve this, but if you need further help, reach out to our team here: Get Support

Best regards!

We were just talking about issues around TWIN displays from the same maker over here:

How do I make my Studio remember which mo… - Apple Community

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Hello bnimit,

For help using an external display with your MacBook Pro, we'd recommend checking out the steps in this article: Use an external display with your MacBook Pro

That should help to clear that up for you.

Take care!

If Samsung does not provide the ability for you to report problems with their products and get Samsung working on a fix, then you have few choices other than to 'Vote with your feet' and move on to a supplier whose devices conform better to the VESA standard, and put the device serial number in the correct field..