It been a long time since I've been here.
I've seen this question asked over and over. But I still can't get a solid repeatable answer.I'm using After Effects CC 2019.

Working with an illustrator file imported into After Effects.
I then "Create Shapes from Vector layer" so I could animate them.
I have them Nested in a Comp set to "Bicubic".
However, I see Shape layer groups can only be set to Trilinear pixel smoothing.
"Interpret footage" option is not available on the comp so I can't change the settings.
The comp is set for 4k then I render to 1080p that helps a little but not as smooth.
The rendering setting is set to Classic 3D and the sample settings seem to have no effect.
My last resort is the put a small amount of Gaussian Blur effect on the Shape layer.

What am I missing?