Cookbook, get HTML.
What’s wrong with that? Why would you use Webdriver.io at all – that’s a browser automation and testing tool. You don’t need a browser to download HTML documents.
Just for the heck of it: about 20 lines of code in node.js can do that.
So you basically download a HTML document, extract its “content” (whatever that may be) just to stuff it back into a HTML document? May be I’m missing something, but to me that sounds like printing a PDF to then scan it back in and convert to PDF.