When looking at how social media affects that of your SEO, I found this particularly interesting and accurate. It takes into account how engagement among platforms and how that affects rankings within Google to what will determine search results.
I believe that it is 100% accurate that everyone should not focus on one platform alone; Twitter requires high engagement, while Facebook requires engagement, and able to spread from there. If a company is working and focusing on multiple platforms, this gives them the option improve (or pick up) where they may not be doing so well on another platform.
Although there is not a set formula for how to improve SEO, and that all depends on the users and workers at the same time, there are many tips and things to keep in mind when looking to build and sway SEO within your favor.