Feature management has been around in Microsoft Dynamics 365 for Finance and Operations for some time now. Before that features were enabled through flighting running a SQL query on dev and UAT boxes (and the DSE team would do it on production).
Now we have a nice workspace showing all the available features and flighting is still around too. The main difference between flighting and features is that flighting is enabled to a selected group of customers, like a preview of a feature.