Import excel into existing list (with data already in it)

RRMX01 I wish MS would add an import button! Edit in grid view sucks doing incrementals when we build a process and have hundred or even thousands of legacy data that we may hide from a view and create "categorized" views to see the legacy data. Lists can have more than 5k so we just hide them to avoid hang ups with form loading. 

A list can store 30M list items, there is literally no need to export items out or archive anything into another list if you just create a yes/no field called "legacy" or "archived" and just hide the dang list items. Performance doesn't get impacted when these paramters are in place and views do not show the "legacy or "archived" list items with filtering. 

That said, it would be nice if MS prioritized this to allow import so we can import and move on and wait for it to be done vs monitoring and spending almost an hour - 2 hours do 100 list items at a time. 

We build automation solutions that sometimes involve tons of legacy records that need to be available for searching or reference, hints why we give them additional views grouped usually by the created by year or something. Just an example.