actually, Yes anybody can, but the problem is what you consider ROI related social media marketing. since if you think ROI is a sales inquiry and you are going to ask us to post all saley posts content, you won't get any engagement, and thus no sale. so the approch is flawed, and can't repair it until you tell me what you selling, so that i can advise a better approach.
IMHO, a better approach is always to have a mix of both paid ads and organic contenting. gone are the days when you could reach mass through posts alone, sinxe now facebook or any other social platforms want you n me to pay for ads beside organic content for decent results.
how you see that? share your thoughts.
Best, Gaurav