Isn't ignored, as far as I've tested.
Hm. Then my (entities on) views are somehow different (I don't know how, normal views actually).
I marked them all, set the plugin to 'set nullable to true' and ran it.
Then I opened some of these entities in designer, and no field was set to nullable.
After that I tried with an entity on a table and it worked as expected...
Anyway, you can modify the plugin. How are you going about that?
Slowly
I don't know how long debugging the plugin would take me, so I bit the bullet and switched the datetime fields to nullable manually...
Maybe I'll find some time in the next few days, but probably there are other things to do
But anyway, thank you for your help.