I like the effect on red stars.
I'm wondering if it is a performance thing.
Theorizing here, I really have no idea but....
If you imagine the scenario of jumping into a system, the star starts of very small and quickly blows up to a huge size.
If stars were being over-rendered at small sizes as in too much detail, it's possible that this has been fixed.
So now the rendering level is appropriate to the size, it's just that there's a slight lag between star size increase and rendering detail increase as whatever calculations that are required is being done.