This is how my resume was (maybe still is, I haven’t looked I years).
One thing I did that I like was after the most recent jobs, the older and less relevant ones were faded a bit. A hover would make them dark and easier to read. When printing a PDF, only the darker more recent ones would print. This let me keep a full record in a single file (mostly for my own benefit), while still being able to quickly and easily print out a single page version.
You could have structured data as json etc within that html, and some Javascript that renders that onto final html. Than add a button (or a URL argument, or print action) that returns final html (including all your Javascript). That way you only ever need to update your structured data while never needing to edit the html itself. You could theoretically even add some interface to update the resume. I am thinking tiddlywiki but for the CV.
May be that's what you are saying in your comment already.
It will be self
I didn't go that route for the resume, but I have made sites that work like that for start-page type sites (I had a drop down menu to swap out different json files being loaded in for various categories). It could work for a resume as well to keep the front end as whatever you want it to be, while not having to re-write your actual work history. Then instead of giving things a hidden-print class, there could simply not be there at all, but still be in the json if/when needed.
That then leads to the idea of having an api endpoint for your resume data, since it's already in json, with an industry standard format. So instead of all these sites parsing a human formatted resume or text file, they could skip the middle man and have structured data to work with. The downside here would be needing to host it somewhere that can deal with server side code. Or maybe this is a startup idea.
One thing I did that I like was after the most recent jobs, the older and less relevant ones were faded a bit. A hover would make them dark and easier to read. When printing a PDF, only the darker more recent ones would print. This let me keep a full record in a single file (mostly for my own benefit), while still being able to quickly and easily print out a single page version.