Even with state, his code is overly verbose and can be expressed in a much more idiomatic way.

    var weAreConnected = Math.floor(Math.random() * 10) > 5;
    if (weAreConnected === true) {
      this.setState({
        isConnected: true
      })
    } 
    else {
      this.setState({
        isConnected: false
      })
    }
  }

turns into

    var weAreConnected = Math.floor(Math.random() * 10) > 5;
    this.setState({
      isConnected: weAreConnected
    });

It's almost like he wrote it in the most obtuse way possible to prove his point. Unless he writes like that normally; If so then I can see where he's getting all these errors from.