It claimed that version 5 supports Apple Silicon natively, but why I still saw it showed as Intel in Activity Monitor?
$ file -b '/Applications/Beyond Compare.app/Contents/MacOS/BCompare'
Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit executable x86_64] [arm64]
/Applications/Beyond Compare.app/Contents/MacOS/BCompare (for architecture x86_64): Mach-O 64-bit executable x86_64
/Applications/Beyond Compare.app/Contents/MacOS/BCompare (for architecture arm64): Mach-O 64-bit executable arm64
I would suggest re-downloading...