I also have the same issue when I try to lunch navicate premium after i update to MAC OS Big Sur
Dyld Error Message:
dyld: Using shared cache: 9F6FFF1F-4096-355B-B037-8DCE73A7AA42
Library not loaded: @executable_path/../Frameworks/libpq.5.dylib
Referenced from: /Applications/Navicat Premium.app/Contents/Frameworks/libecpg.6.dylib
Reason: image not found