The simulator changed at some point (a few releases ago perhaps?) and no longer opens URLs directly like a mac app or declares itself as capable of doing so. Before then, Hype had some extra support to have this work even!
But in investigating just now to figure out if there’s a new way, it looks like you can use the terminal command:
xcrun simctl openurl booted "http://URL_HERE"
This can work with Hype’s preview server URLs, and I’ve added an item on our todo list to use this in a future version so we can restore the functionality.
Instead of FTP’ing, you may want to check out using Hype Reflect. It lets you send Hype documents to your iOS device for previewing. It also has an open in Safari button that may help. (especially since we need to update some of the screen sizes for modern devices!)