I would say that the man wasn't lying when he called Jesus "good." He seems not to have realised the full implications of calling Him good, that if He is truly good, He is God. The man was mistaken, but that doesn't mean he was lying. If a child at school spells a word wrongly, or gets the answer to a maths problem wrong, is he lying? Of course not. Lying involves knowing the truth, but saying something else.Didnt someone try to appease Jesus? I'm pretty sure The guy said To Jesus calling him Good sir. Jesus didn't have tell him it was a lie, Jesus just spoke the truth. and Not to make excuse saying Jesus is God, Jesus was being real a man and spoke as a man of God to another man.
It's up to you to see if Jesus was saying he not speaking the truth .
Certainly your example of the man calling Jesus good does not mean that all men are liars.