Although Vision is seemingly alive and well, it would make sense for the series to focus solely on his death.
At the moment in the Marvel Cinematic Universe, there is absolutely no way to bring Vision back to life.
Because of this, it is fair to assume that Vision, in WandaVision, is just a construct of Wanda’s powers, meaning he is not really alive.
Many instances in the Marvel Comic Books have shown Wanda’s powers reflecting her emotional wellbeing.