Compilations was made in a Docker Ubuntu x64 image. There the results:
python3 -m nuitka --follow-imports -j 4 --plugin-enable=multiprocessing kapow.py
23MB
0.068 sec
No incluye las librerías del S.O. y no es standalone
python3 -m nuitka --follow-stdlib --show-progress --standalone --python-flag=no_site --follow-imports -j 4 --plugin-enable=multiprocessing --lto kapow.py
30MB
0.068 sec
Resulting binary doesn't include O.S. libraries and it's not standalone
pyinstaller kapow.spec
8.2 MB
2.7 sec
Resulting binary doesn't include O.S.
pyinstaller -F kapow.spec
14 MB
14 sec
Resulting binary include O.S. libraries and it's standalone