Just wondering if I should avoid social media apps altogether or if using apps + certain settings is the same thing.
Good questions and I don't really know the answers but I would be inclined to do a fair bit of Googling to find out and maybe start off with a search for something like:
mac how to protect youself if using social media
Then add some more specific searches that more match your usage and look for the answers or at least the comments some may provide.
And I am sure some members will be able to provide you with some good information based on their experiences.
As far as I know, Apple does a pretty good job of protecting a users info and data as long as the user doesn't do anything stupid to break that protection. And we read and hear almost daily in the news of many individuals who do just that. But it's hard to fix stupidity.