I am getting the same issue. I have put the refresh command multiple places in the app to try and force a refresh as I need to get the new data to display straight away. For testing going into task manager to restart the service is fine, but using it for production wouldn't work as I would need to be refreshing it every two seconds as users are trying to use the app. Has anyone else found a solution to get it to refresh quickly?
I am also experiencing the same issue. I refreshed DataSource, Reconnected my SQL Server, cleared my browsing history, and yet i still get the same problem on the delay for updating changes in Datasource. It should not be as difficult as this when refreshing sql database via powerapps otherwise we will be experiencing delays in developing the app as well since we could not find the new column we have added in the datasource.