I agree for the most part. I would like to point out that fish farms are actually very damaging to the ecosystems that they sit in. The excrement ends up dropping down in single locations, burying the seafloor in it. IIRC, this often leads to the oxygen levels in the water dropping, which further kills off the surrounding aquatic life.
EDIT: more context
Correct. there was actually a period of time when trees had no predators or scavengers that could break down their body matter. They actually likely caused mass extinction events during that time.
Sources: Hank Green talking about it (just a fun video, I wouldn't take it as gospel necessarily)
IFL Science article (I cross-referenced this with multiple other articles and it seems to talk about a cempletely different mechanism for mass extinction to occur)