The bug still exist and it has marked as Won’t Fix because it has been so long!
Now that workaround only works if you want all particles the same color at the same time. Considering defining a color is a basic thing of a particle system it would be much appreciated if anyone can fix this issue.
I have not tested yet if the same bug exists with Niagara, maybe if its working there the fix can be taken over for the regular particle systems.