This has been in beta for quite a while I believe. I don't know if Google Data Studio has been around for longer, but I remember looking at Quicksight at a previous employer in 2013.

IMO it is more a response to Microsoft with its PowerBI + DataZen products.

The Google Data Studio is only for dashboards (i.e. static visualizations) these other tools offers standard BI operations like rollup, drillup, pivoting and etc.