The Russians stopped angling their cold launched VLS when they figured the probabilities of failure happening is too low to bother, based on historical record. The Chinese may also have arrived to the same conclusion. These also include land based examples.Regarding "hot vs cold" launch,
What happens if the missile fails to fire its rockets in time during cold launch? In the 052C the VLS is angled and the missile would likely just fall into the ocean. But what about the VLS in the 052D and 055 (as well as several Russian systems)? The missile would fall back onto the ship. In hot launch, any missile ignition failure would mean the missile just sits in the VLS.
Like to know your thoughts on this.