Currently there is only one method of determining exactly where a bullet died, checking if the bullet is dead every few frames and returning the last known position if so.
For one or two or ten bullets this is absolutely fine in a debugging environment, however, utilizing this in large firefights with sometimes upwards of 1000 bullets in the air at once has the potential to slow any clients running this check down to unacceptable levels.

VBS has had this issue solved for some time in the form of an EventHandler "AmmoExplode" which fires upon bullet destruction. [https://resources.bisimulations.com/wiki/Category:VBS:_Event_Handlers#AmmoExplode.2FAmmoHit]
An in-engine solution such as this provides superior functionality for potentially near 0 performance cost (1 extra if statement just before the bullet is removed?)

If this were implemented any mod which previously required modifying the bullet, or adding additional effects, on impact to reduce what would be a large performance impact to 0, potentially improving client AND server performance.
Additionally this opens up many new opportunities to statistic or replay systems to track rounds with no performance impact, something that just can't be done as it stands.