No, the job of the Supreme Court is to be the last court of appeal to uphold the US Constitution and laws passed under it. It does that by deciding cases. Setting precedent is a side effect, which can be helpful if it reduces the need for future cases of the same type to have to come to the Supreme Court again, but is not the primary purpose.
The result is that precedent is the most effective tool that the Court has to serve its purpose. And therefore that is the most important thing that they do. And they are extremely highly aware of it.
And all 100% of its decisions decide cases. So more of its decisions decide cases than set precedents. So your argument is a non sequitur.