building for iOS Simulator, but linking in object file built for iOS, for architecture arm64

Hi,

I have found multiple questions on this topic but none of the proposals solves my problem so please stay with me on the description below since I am obviously missing something.

I have an iOS Framework that links with multiple static libraries from a C Open Source project using "Other Linker flags" and "Library search paths". These .a files are all fat binaries including arm64 and x86_64 versions.

This Framework is later used by a regular iOS app after being packed into an XCFramework (do note, when generating the XCFramework I use EXCLUDED_ARCHS="arm64" for the simulator build since a long time and I think this is also wrong).

Everything works fine on device but I have never gotten the Simulator to work on my M1 Mac and now I am trying to fix that but without success, when trying to start the simulator on M1 I get this error for the first fat .a found:

building for iOS Simulator, but linking in object file built for iOS, for architecture arm64

I do not want to exclude arm64 arch for the simulator as suggested in some posts since I want to be able to run the app in arm64 mode on the Simulator. Also, when starting the simulator on my M1 (not using Rosetta) I am expecting it to run in arm64 mode so then it makes no sense that it complains that the static lib is an arm64 lib right?

I have tried changing Build only active archs and other suggestions but nothing has helped. I also checked the fat binary used from the framework with otools as suggested by @eskimo in another post and it spat out this: Load command 1 cmd LC_BUILD_VERSION cmdsize 24 platform 2 minos 13.0 sdk 15.4 ntools 0

which I think is correct, PLATFORM_IOS.

I assume the arm64 .a file that runs in the xCode Simulator is the same as the arm64 .a that runs on device right? Or do I have to build arm64 for the Mac platform to run the iOS simulator on M1?

Very grateful for any ideas on what might be wrong.