Found the reason. Sorry, it was my fault: I installed the wrong MAC version (SweetHome3D-7.3-macosx-10.4-10.9.dmg) instead of appropriate (SweetHome3D-7.3-macosx.dmg) for my MacOS 14.4.1 machine by simply clicking the green SourceForge download button.

By the way: Are there any plans to provide a native Apple Silicon arm64 build?