What does "just" mean here?

Rebecca

"Just" in this sentence means "only" or "simply." He is using "just" in a surprised tone; he can't believe that the filmmakers only used car oil to portray syrup instead of using actual syrup. Ex: I just want some alone time. Ex: I just want to get to know you. Ex: She just likes her tea with honey. Ex: He's just started his journey.