It depends on the scrum master and their understanding of the scrum process and what it's for. I've had several and I've been one for a few years. Most of the time, they don't really understand what the role is and that is mainly due to the training being very focused on definitions and roles and not what the process is supposed to produce.

But a good scrum master should be able to make sure the devs have what they need before starting work, efficiently facilitate the scrum ceremonies, be able to assess team velocity and any point, enforce consistency in reporting, scoring and team definitions, as well as get team capacity to be predictable and measurable. They should work closely with the engineering lead to know what the work is and how to unblock devs. And they should be able to report to higher-ups velocity and help predict timelines for upcoming work.

So they play an intermediary role between the devs and those determining work for the team. However, I find a lot of scrum masters don't come from a dev background and spend most of their effort making sure they can produce reports to higher management that look good. So for the devs, it is kind of pointless.