chances are it's not going to be fixed outside of toady changing "It was inevitable" to something that written pleasant to the players who seek fame and glory but still means the same "we don't have any historical data to emote over this news."
This would be the wrong way to fix it, because replacing that message by another will lead into the same problem : same npc answer to everything that are reported to them.
Considering you can report limited amount of events, while of course it can take time, it would be a lot better to get
- a reply appropriate for report of *dead npc*
- a reply appropriate for report of *dead bandit*
- a reply appropriate for report of *dead bandit overlord*
- a reply appropriate for report of *dead animal*
- a reply appropriate for report of *dead night creature*
- a reply appropriate for report of *dead monster*
- a reply appropriate for report of *dead megabeast*
- a reply appropriate for report of *dead fogotten beast*
etc...
With the reply being on a negative / neutral / positive tone depending on the npc affiliation in regard to the dead and on the npc level of stress/emotion.
It wouldn't be perfect but at least the player would feel the world less dead if people acknowledged a report by something else than the same exact reply or variation of that reply like in df2014 and had instead something to say that is appropriate to the report, whatever it is in negative/neutral/positive way.