I have worked on the front-end of PlayStation 4 and Xbox One single-page applications.
You can preview the Xbox One version here: https://www.microsoft.com/en-us/store/p/ubisoft-club/9pgq6g1k5qd7 or you can watch this video:
Thread related to the project: https://twitter.com/sylvhama/status/1046820308647387141
webpagetest result (first view vs repeat view) From: Sao Paulo, Brazil - Chrome - DSL: https://www.webpagetest.org/result/181219_MP_0cd57a253bb1d8acc740f3a563192764/
I also have developed a platform that allows anyone to implement its own tools using React, Redux and material-ui. It offers a lot of components to avoid re-inventing the wheel (e.g. a search bar to find a game). It's a Progressive Web App, it can be be used as a desktop app and has very good performance.