I think web browsers need to get back to basics and do their original job as "The User's Agent" rather than what they are today: Instead of being a tool to fetch and display hyperlinked text, they've morphed into this API platform built for web companies to control down to the pixel what users see in their browser window.
Today browsers barely give you a few blunt tools to control your own browsing experience: Javascript on/off, Styles on/off, and so on. I want a browser that 1. fetches YouTube's HTML, 2. understands it to be essentially a bunch of links to video URLs, and 3. present me a simple list of those video URLs that I can click to watch or download. I don't want my browser to act against me by being a platform where YouTube executes god-knows-what on my system to render everything the way YouTube wants and to show me things that YouTube wants and push content that YouTube wants to push. Put the user back in control.
Same for Reddit. Browser should fetch Reddit's HTML, realize it's essentially a list of links, and simply display those links, ignoring all the other shit that comes down in the site's HTML, CSS, and JS.
I realize that step #2 above is hard and probably magic at this point. But that's the direction I'd like to see browsers go. Stop adding even more APIs that companies can use to control my browser.