Storing and processing data locally in a user's browser without using server API actually can be a valid reason to build a client-side application. But they jus

Storing and processing data locally in a user's browser without using server API actually can be a valid reason to build a client-side application. But they just use one megabyte of JS code to implement client-side rendering for JSON data received from API. Serving a 10 Kb HTML page is obviously a better solution. I see no single benefit from using complicated JS framework here.