Correcting Thiessen Polygons output from ArcMap

I am try to divide irregularly shaped polygons at specific points. I don’t have any fields that inform the angle at which the polygons should be divided. Based on the Split polygon based on point feature at GeoNet, I am trying the Thiessen Polygons + Intersect approach, and it’s almost working.

In the screenshot below, the orange is my "irregularly shaped polygon" and blue at the Thiessen Polygons created from the green points.

Below has a general sketch of my desired outcome, the gray polygons, just sketched in PowerPoint.

Is there a way to make the Thiessen Polygons more like the gray polygons than the blue polygons?

Ultimately I am interested in the interseciton of the orange polygons and gray polygons.

I am using ArcMap 10.7 with an Advanced level license.

import arcpy

#mypoly = filepath to my polygon SHP
#mypts = filepath to my points SHP
#myoutput = filepath to save Thiessen polgons output

arcpy.env.extent = mypoly
arcpy.CreateThiessenPolygons_analysis(mypts, myoutput, fields_to_copy='ALL')