Matlab circle symbol has jagged edge with thicker linewidth

Question

I ran into this problem that when I set the linewidth property of a series of circle symbols to 3 or larger, the edge of the circle appears very jagged, like shown below:

Does anyone know how to fix this?

I saw a very old post that discussed a similar problem using the function scatter, but I can't get the recommended command to work, probably because it was a much older version of Matlab.

Any help would be really appreciated!!