As far as I know, the science on this is far from settled. There is no consensus and the evidence in favor of a trophic cascade in Yellowstone came predominantly from two studies done by the same team/person. Later studies failed to replicate findings.
Do wolves fix ecosystems? CSU study debunks claims about Yellowstone reintroduction
Do wolves fix ecosystems? CSU study debunks claims about Yellowstone reintroduction
https://eu.coloradoan.com/story/news/2024/02/09/colorado-sta...
A good story: Media bias in trophic cascade research in Yellowstone National Park
https://academic.oup.com/book/26688/chapter-abstract/1954809...