It’s ambiguous what you mean by “cut,” but Taco Bell has cut their ground beef with soy based product for years. The biggest question is how far can meat preparations be diluted with fillers... I don’t think we have to eliminate meat to have a meaningful impact (e.g. a 50% reduction in meat consumption would cut about 3% of US greenhouse gas emissions.)
That's exactly what I mean by cut. As the filler gets better (which is certainly the long game for synthetic meats) you can keep upping the amount as long as the end user can't tell. You're very right about diminishing returns and not needing to eliminate meat fully though.
