Valid point, but leaving thins as is does not seem like the optimal solution. Maybe the mods could occasionally post examples of removed spam/bot content, for transparency and awareness. Leaving this to random users can end with more mistakes and actual abuse.
Also, the troll/bot comments and discussion around them will less disturbing outside of the intended context (where they were posted to cause disturbance or misinformation).
I hope they can be held accountable for mistreating those 'transplants" (what an ugly word!) too. But I guess that would be easier here in EU than in USA.