This is not consensus. There are lots of anomalies in what we observe in the cosmos. Here someone links two of those to a speculation about extra dimensions. It

This is not consensus. There are lots of anomalies in what we observe in the cosmos. Here someone links two of those to a speculation about extra dimensions. It would get interesting if they have predictions that can be checked. A promising new theory should fit known observations, explain previously unexplained phenomenon, and predict something testable. That will be difficult to judge as a layperson.