Is there an easy way to import textured 3D geometry from Maya into Nuke?
This still isn't as easy as it should be, but the way forward is to export your geometry as Alembic.  It supports many textured objects, and even animated sequences.  Depending on your version of Maya, you may need to install a plugin, but it is much better than dealing with OBJ and FBX as the interchange format in most cases.