Default SAN routes on RHV-H deployment

Network manager is so messed up RHEL 8.

I have two network adapters. One for LAN for the management.
Second is dedicated to the SAN.

It was discovered that with RHV-H (4.4) the SAN interface HAS to have a gateway when provisioning. (something about the HA broker service)

If I reboot, the SAN interface throws in a default route that takes RHV-H offline.

I removed all route paths from the interface with NMTUI.

I deleted the routes network script for the interface.
I added the line DEFROUTE=NO to the interface.

Network scripts are wiped and reset on reboot always goes back to DEFROUTE=YES. The NMTUI settings don't stick. IPv6 always goes back to enabled.

WTF is going on? I hate Network Manager. Is there some learning path class that covers how this all works?