Earlier quoted context omitted.
The solution is to use https://qubes-os.org . My daily driver, can't recommend it enough.
Qubes is one of those things that, I think, everyone knows is better but it seems just far enough away to not want to change. How big of a change is it? If you are, say, a Linux terminal native can you just pick up and run?
There's some learning curve for features which exist for valid reasons, especially around communicating between domains. For instance, copy-and-paste between qubes requires extra steps. Plugging in a USB keyboard or mouse doesn't just work - you have to authorize it first (just click the OK button using a PS/2 mouse, or laptop's touchpad). You have to learn how to move files between qubes. USB drives, cameras, and microphones aren't globally available to all applications - you have to attach them to a qube first. You can install software using apt-get inside a qube, but it won't persist across reboots - you have to update the OS template.
I want those extra steps and complications - they are features, not a bugs! The first few days you'll be looking things up in the FAQ. After that it's pretty easy.
There are a few sore points that don't go away. You don't get GPU acceleration in your web browser, so rendering is slower. Gaming is not an option. Your application qubes live behind a firewall qube, so things that require network broadcast like Chromecast won't work. Those are fine for me but not for everyone.