I would definitely suggest NestJs over other options because NestJs gives a lot of tooling.
it would definitely suggest NestJs over other options because NestJs gives a lot of tooling & it gives a lot of functionality out of the box. If your team worked with angular 2+ then it will really easy to learn.
You can use NestJs with microservice architecture.where you can also use socket.io for web socket. you can use MongoDB (For real-time data) & MySQL for customer management.if you don't want to implement websocket.you can use firebase.it gives realtime database & firestore.which can handle millions of connections and scale it up.
