getting a list of points that make up an edge using the draw environment.

Well, you may use dump to print entire information about picked TopoDS_Edge and look for PolygonOnTriangulations, Triangulations, but this would require some parsing if you want to do something with this information.

Otherwise, there are commands triepoints, which generates a list of VERTEX out of tessellated EDGE, and pnt command to print coordinates of each VERTEX:

pload MODELING VISUALIZATION
pcone c 100 10 50

# remove existing tessellation if needed
#tclean c
# tessellate shape with specified quality
incmesh c -prs

axo
fit
# pick one edge to dump
explode c E
donly c_1

# dump entire shape - see PolygonOnTriangulations and Triangulations sections
#dump c_1

set pp [triepoints c_1]
foreach p $pp { puts [pnt $p] }

Possible output:

Draw[27]> set pp [triepoints c_1]
c_1_1 c_1_2 c_1_3 c_1_4 c_1_5 c_1_6 c_1_7 c_1_8 c_1_9 c_1_10 c_1_11 c_1_12 c_1_13 c_1_14 c_1_15 c_1_16 c_1_17 c_1_18 c_1_19 c_1_20 c_1_21 c_1_22 c_1_23 c_1_24 c_1_25 c_1_26 c_1_27 c_1_28 c_1_29 c_1_30 c_1_31 c_1_32 c_1_33 c_1_34 c_1_35 c_1_36 c_1_37
Draw[28]> foreach p $pp { puts [pnt $p] }
9.9999999999999858 -2.449293598294703e-15 50
9.8480775301220653 1.7364817766693008 50
9.396926207859071 3.4202014332566821 50
8.6602540378443749 4.999999999999992 50
...