We are trying to update an Excel list and have the updates automatically pop up in SharePoint. Is this possible and if so, how?
If you want the Excel table to create each time a new SharePoint list, it is possible out of the box: Create a new SharePoint list from the modified Excel file.
If you want the same SharePoint list to be updated each time you modify the Excel file, it can't be achieved without either custom development or using a third party tool. I would naturally suggest Synchronizer for Excel and SharePoint, as this product is edited by SoftFluent, my employer.
Without the need for any heavy coding or third party tools you can look at the below approach:
Place the Excel file in a SharePoint Library you can track it for changes from Flow and then launch an Azure Automation Runbook Script (Powershell) that will do the import.
This is a relatively straight forward approach if you can write the powershell script.
Just like cook said, if you want to update SharePoint list excel change, you may need to put the excel in an OneDrive library. Then you can create a flow to fetch the updated data in your workbook and update your SharePoint List.
Here is an sample you can refer to: Regular Import of Excel Sheet To SharePoint List