[basch]

>as the alternative to sharepoint for new projects/working groups.

>Team's live editing functionality of excel files

Teams is a Client, SharePoint is the server. When you use Teams to view a file list or open an excel file, all its doing is streaming the SharePoint web interface, like an iframe. Teams, as far as the file side goes, is a new form of browser chrome (the toolbars not Google Chrome, albiet Teams is also based on electron aka Chrome.) for SharePoint, instead of the Modern SharePoint Web interface.