Netflix does work with lineage-14.1-20190202-nightly-kingdom-signed.zip version just fine, which has SELinux protective, and w/o magisk.Some applications checks their running environment and requires non modified ROM so it's working only on stock Google certified ROM.
Magisk can help with that, but it's workaround and can stop working anytime.
That's why I thought this might be the SELinux permissive which is making netflix to not work with the 16 release.