Unable to lock smart sheet filtered data in excel

Make a report. Use the report builder to populate your report with the records that you would see in the filtered sheet. Export the report records to excel. 

I don't understand the issue with locking … can you explain further? 

I'm on an enterprise license.  I use the live data connector to link excel with smartsheet sheet(s) and report(s).  It's has limitations (sharing/security) but it eliminates the need to constantly export data. A plus is that the excel sheet can be refreshed to reflect changes in smartsheet data.