Trichoderma is a fungi considered GRAS (Generally Recognized as Safe), but I think that this microorganism have other important uses such as biocontrol agent and production of enzymes, aromatic compounds, antibiotics, etc. I think there are other fungi more profitable to enrich some substrates.
Trichoderma is okay and very suitable in feed production and also considered as GRAS. The processing method however had to be well spelt out so as not to loose the inherent nutrtional value
Trichoderma has been used to biodegrade lignocellulosic materials in livestock nutrition. So far so good, no side effect or toxicity/intoxication has been reported in animals fed Trichoderma treated diet. It is among the GRAS.