What surprises me, is that the blurring of the lights in the f8 is rounder than the f1.4. Chances are I have something else wrong with my settings, and can't figure out what it is.
Ah! Now I understand what you think is bokeh.
Your lights are rounder in the f/8 pic because are badly overexposed, not because they are out of focus. And they are overexposed because the overall light vs. f/1.4 version is something less than double (f/8 3.2s ISO400 vs. f/1.4 0.5s ISO100).
In f/1.4 version you can see some of the circles typical of OoF light points if you look on the left of the last light.
However, better to do these experiments in the day. Go closer to that amphora and the rest will be more blurred (bokeh does not mean just "light circle").
If you just want some circle of confusion, shot some defocused
point of light, i.e., something much smaller than those lights. No surprise people do this with Christmas trees

.