When I was playing I noticed that the singularity ability seemed to clear the smoke from the grenades, is this just a coincidence or does it have an effect on it?
I tried multiple attempts, and recorded every attempt (for science). Although I could have sworn that I have seen this effect myself, my guess is the smoke grenade ends its duration and if a singularity is present, there is a chance it gets "sucked in" as an easter egg animation.
However, the singularity itself does not specifically reduce the time of the smoke grenade. Here is a video of one of the attempts, showing a clear lack of singularity vacuuming.