In the link below it says #3 "do not send synopses to screenplay agents or movie production companies."

Are they saying we should send queries instead or not send anything? I had read if we cannot find ourselves an agent, to then go to the production companies. Is this incorrect? And will any give me the time of day? I recall reading on some entertainment lawyer website that sometimes it's easier to get an agent when you have an interested production company. At that point do I even need an agent though? Any help appreciated, thanks!