John Mueller from Google was asked if a salience score matters for SEO. His response was "Where do you see that?" Reading into that, I suspect he means, no - but where is that myth coming from.
The definition of salience is the quality of being particularly noticeable or important; prominence. But if you dig a bit, you can see it mentioned in the Google Cloud AI docs around entities. Google writes "The salience score associated with the entity in the [0, 1.0] range." The salience score for an entity provides information about the importance or centrality of that entity to the entire document text. Scores closer to 0 are less salient, while scores closer to 1.0 are highly salient.
Here is how it looks like in JSON:
Conceptually, the more important, noticeable or prominent probably does help you rank because it is easier to get links and other PageRank signals. But it is interesting that an SEO would ask the question as he did.
Here are those tweets:
Where do you see that?
— 🍌 John 🍌 (@JohnMu) December 14, 2019
I wouldn't worry about that. Feel free to play with our APIs, there's lots of cool things you can learn & make with them, but don't assume that everything is used 1:1 in search.
— 🍌 John 🍌 (@JohnMu) December 27, 2019
Have you seen SEOs talk about salience scores before? Here are some things I found online using the old fashion Google search for [salience score seo].
Forum discussion at Twitter.