Kid not speaking in Daycare

Our 2.5yr old talks at home. He articulates well with obvious grammer mistakes like " I no like it". He conveys what he wants properly. But daycare teacher told he doesnt talk in Daycare. Just yes or no answers. They had an assessment recently where people suggested speech therapy for him. I personally feel kid ks shy and will be ok once they reach a certain age. Is this a cause of concern? Should we do something about it?