Facebook is a great way for photographers to interact with people. There are very few limits to the number of people that potentially can see your work. You can create a separate page for your business and offer some work for sale. Facebook ads can help you reach a targeted audience, and more. I enjoy my presence on Facebook.
There is one feature Facebook would like you to use that is clearly not in your best interest, the Facebook App for your phone or tablet. This app asks you to give it too much access to the data and features your phone has. By giving the app all the permissions it asks for, you are agreeing to allow it the ability to spy on you whereever you are and whenever it desires to do so. Among the permissions you give it are access to the microphone (it can eavesdrop on your conversations), the cameras (it can see whatever it is able to whenever it chooses), and your location (it knows where you are at all times). Any and all of that information is able to be sold to the highest bidder or shared with government agents. I have never downloaded that app, and probably never will, even if it is changed to eliminate the undesired features.
I do use Facebook from my computers and from the browser on my tablet, where I can control the information I allow Facebook to collect from me. I find it a convenient way to communicate with friends.