This post comes courtesy of Susan Bradley, in that she highlighted the issue to me. In turn it was highlighted to her via TechSpeeder.
The issue is a relatively simple one, in previous versions of Essentials, visiting http://server or http://server.remotewebaccess.com it would automatically redirect you to the RWA Login page at /remote. In 2016 this is not occurring.
In 2012 R2 this behaviour is controlled via default.aspx in particular, this line.
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="Microsoft.WindowsServerSolutions.Web.RootSite._Default" %>
Looking at the Content of the Default Web Site in 2016, we can see the standard IIS InetPub wwwroot folder. This is odd because usually in Essentials that path has been updated to C:\Program Files\Windows Server\Bin\WebApps\Site.
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