This sounds like an issue I vaguely recall between fallback and accelerated graphics. I think it was fixed in 5.99.
Are you using accelerated graphics (Preferences menu -> Modern Toolset (Accelerated))? If not, does the dots setting look better using accelerated graphics?
edit: I think this is what I was thinking of: https://gitlab.com/kicad/code/kicad/-/issues/5832
doesn’t sound exactly the same, but I’m still interested if changing to/from accelerated graphics helps.
Does changing the zoom level change anything?
Also, a screenshot and version info would be useful.