At the moment, maintaining several major platforms at once is extremely difficult, because each social network now has a very strong anti-fraud system. Even supporting just one platform is challenging, let alone multiple. If I were in your position, I would start with a single platform first and evaluate how complex it really is.
But even if everything works well right now, it doesn’t mean that tomorrow, for example, Instagram won’t change its algorithms in a way that makes your software stop working instantly and then you’ll have to spend a lot of time adapting to the new rules.
