Why am I not able to run a website which ‘requires javascript’
The problem is that the web site is simply broken.

When your browser connects to a web site it sends along a so called "user agent"-string, which specifies which browser, browser version and operating system, you're using.

That specific web site uses that information to only show the real page to user agents that it allows. Others will be shown that incorrect page telling you to enable Javascript - which is misleading.

In order to access the web site from an iPad, you'll need to a use a browser that allows you to change your user agent. That is not possible with the standard Safari.

If you're on a Mac, you can enable the Developer menu in Safari system preferences. From the developer menu, you can choose "User Agent => Google Chrome - Windows", and then you get to the real page.