Recently, I noticed more and more colleagues and friends are getting promotions and raises with their tech skills being on pair with the rest of the team, so I assume (hopefully right) that those soft skills make a difference.
It's not the best piece of writing necessarily, but it is easy enough to follow, and the author does a great job describing some dynamics that take place at various points in a given career, and what you can do to optimize your relationship with those dynamics.
https://www.amazon.jobs/content/en/our-workplace/leadership-...
For most of the rest of us "average" types, the best way to differentiate is with soft skills. There are MANY, MANY resources - pick one that leads with empathy, the specifics probably don't matter as long as you are ingesting new content and applying it to your day-to-day (don't forget to get a feedback loop to ask others how it comes across to others!)
Ultimately, to paraphrase Maya Angelou, people won't remember what you said but they will remember how you made them feel. Clarity, kindness, and pulling in the same direction as your teammates -- I think these are the goals of developing soft skills.
Also, don't forget non-programming hard skills like project management and written communication. Not sure that's really a soft skill - but it does matter in how competent you appear.