And yet, story points are used to estimate how much work a team can get done in a sprint, which is a time measurement... and they are used to track velocity, which is used by management to figure out when a project might be completed (also a measurement of time).
"Oh, story points are just about the complexity"
Oh really? Why does complexity matter, if not to function as an indicator of how long something might take to finish?
Anyone who is telling you that story points aren't directly related to time estimation is either confused, or lying.
Absolutely, story points are used as a component in the estimation of time.
Story points on their own are useless though; they are an abstract thing that only means anything to the team and it’s velocity.
A good analogy is that they are an estimate of distance. Knowing roughly how far something is away does not tell you how soon you will get there. You can only do this by working with an average of how fast the team can go.
If the team is terrible at estimating distance, then the velocity will reflect that and gradually self-correct.
Story points are like BMI: They're meant to be accurate enough that, when you aggregate them over a whole bunch of items, you end up with a reasonably reliable time estimate. But they're a terrible measure of time to complete an individual task. They were never meant to be such a thing in the first place.
That's why the canonical Scrum books always say that the PO can use story points to (roughly) estimate completion dates, but the development team should never use them to figure out how many items to accept into the next sprint.
"Oh, story points are just about the complexity" Oh really? Why does complexity matter, if not to function as an indicator of how long something might take to finish?
Anyone who is telling you that story points aren't directly related to time estimation is either confused, or lying.