PowerBI doesn't update in adding new rows Excel

As a new user (6 months) to Power BI with the same question, I'm surprised by the answer often provided, which is to format the Excel data as an Excel Table instead of a conventional Excel worksheet.  I don't often use Excel Tables and don't prefer using Tables - why is this not portrayed as a major fix needed for Power BI?  If Power BI can import data from an Excel worksheet, can't it provide for the most basic of updates to that same worksheet (like adding rows)?  Does Microsoft have in the works to address this?  All that said, if I have built visuals via a conventional worksheet, and I wish to deal with the issue by changing to an Excel Table, do I need to start over and rebuild the visuals?  Thank you.