OS

There is no "best OS" for numerous reasons.
First of all, what would be optimal for your setup depends on a lot of factors, especially your level of experience, what hardware you run, and what you plan on doing
Personally I prefer minimalist Linux OSs for desktop (currently running Gentoo) and OpenBSD for server. Your preferences and requirements are your own however, and you should really be doing your own research

ok, let's turn this into a comprehensive de-kiking thread.

OpenBSD is the best OS in my opinion. It's very easy to use and everything just works. Very lightweight, yet it is full featured. So many OS's ship without proper developer tools. That's not the case with OpenBSD. It comes with everything you need.

Just add a few packages to get a browser, email, client, and media player. Done.

Don't use a smartphone or a tablet.
If you must use an Intel or AMD system, use a librebootable one and install Libreboot. Otherwise, use an ARM system that's not susceptible to Spectre/Meltdown.
Install a minimal Linux OS and secure it.
Browse the Web as little as possible, and when you do, do so through Tor.
Do not run js on your machine.
Never use social media.
If you must use email, host your own.
Don't shop online. When you shop in person, pay cash whenever possible.

If you're a gamer (excepting old non-internet-connected games) you're kiked.
If you use social media, you're kiked.
If you shop on Amazon, you're kiked.
If you use Discord, Spotify, or any other of those spying services, you're kiked.
If you use a FitBit, you're kiked.
If you use Windows or Mac, you're kiked.
If you use Linux but don't take steps to secure it an anonymize yourself, you're still kiked.
If you use an Android phone with LineageOS, you're kiked. If you use a phone with Replicant or CopperheadOS, you're still kiked,, though slightly less so.
If you use a stock Android or iPhone, you're so thoroughly kiked that you might as well change your name to Schlomo Talmudberg and enroll in a yeshiva.

CopperheadOS

Soooo...I've got some bad news...

Don't be pedantic.

github.com/dan-v/rattlesnakeos-stack

install gentoo

:^)