Windows 10 Pro, I'm waiting for end of life in a couple of years to migrate to Linux. Depending on how it goes, it'll probably be a one way trip.

I use Gentoo because it's quite customizable. What's more, building a whole system from source is more secure😄.

Linux all the way, using OpenSuse

Windows 10 + linux mint dual booted on my desktop which is my current main, but I have windows 11 on my laptop that will become my main computer because college. Unfortunately windows 11 is required, i dont even know if stuff like solidworks that i will have to use would run on linux. I am also just more used to windows in general

mac for working, windows for gaming, linux for serving

EndeavourOS on my laptop, Pop!_OS on my gaming PC.

Kubuntu on my Laptop, Windows 11/KDE Neon dualboot on my gaming pc.

I'm not sure which one is my main. I have an old MacBook Air, haven't updated the OS in a long time because I got tired of MacOS becoming merged with iOS. I have a desktop that dual boots between Windows 10 and Ubuntu. I use them all about the same amount. Honestly, I use my phone more than either.

Windows 11, but I'm currently playing around with different Linux distros trying to see if I can finally get rid of windows for good.

Arch on desktop and laptop, debian on server.

Have to use Win 11 on my work laptop though

Pop OS on my System 76 desktop (Thelio Mira). Couldn't be happier with it.

Kubuntu FTW

Q4OS, a very user-friendly Debian-based OS.

Windows on PC for gaming, Linux on work laptop for development

Pop!_OS (Linux)

I dual boot Arch Linux and Windows 10, which came preinstalled and is pretty much only used for games at this times.

Windows 11 for my gaming PC. Debian running KDE Plasma for my work PC. Debian without a DE for my various home lab PCs.

EndeavourOS with GNOME!

Ubuntu

Pop!_OS for desktop, FreeBSD for server

I use arch on my laptops, debian on my servers, and I recommend fedora to others. I'm also nix/guix curious.

macOS for both work and personal use

I've been using Windows 11 and Ubuntu with dual boot on my laptop, but a few days ago I tried Linux Mint, and it's awesome. Now I plan to switch from Ubuntu to Linux Mint.

MacOS Ventura

Windows 10 but I do most of my work in an ubuntu 22.04 VM in virtualbox. But use windows for games and casual use.

Server runs ubuntu 20.04 server which has a bunch of services for my network and my main storage.

Laptop runs ubuntu 22.04 desktop. It's an old laptop so I'm using ubuntu to extend its life.

Windows 11 for gaming PC, Windows 10 for work laptop, Mac OS for personal laptop and Fedora for my old laptop. Also using both Ubuntu and Rocky Linux for servers. Steam Deck is still on Steam OS, Pi's use Raspberry Pi OS (aka raspbian). I don't really have a 'main' computer as it mostly depends where I am and what I'm doing.

I'm pretty comfortable with any OS at this point, even on mobile devices (both Android and iOS/iPad OS). I'm not a big fan of Windows but it pays the bills working in IT. I was in the process of migrating servers away from Ubuntu and onto Rocky (rip CentOS) although with the recent changes in Red Hat Land... We'll see how the rest of the migration progresses.

GNU Guix

Windows on desktop, Mac on laptop (altho likely switching to Framework with windows soon)

Debian Stable (Bookworm)

Windows 10 on my main (gaming) PC (honestly I would probably upgrade to 11 by now if I didn't need to do a BIOS update), and Ubuntu on my computer in the living room. I would try a different distro, but honestly whenever I need a guide to do something on Linux they're always written with Ubuntu and it's default commands and packages in mind so it's just easier to work with

Mint Cinnamon On my gaming PC windows 10 on my decal printer/cutter machine and Zorin Lite on my old laptop

My main system is running Windows 10

It works great for everything I need and as long as I don't enable the TPM in my motherboard settings I don't have to worry about it upgrading itself to Windows 11. Unlike when my system upgraded itself from 8.1 to 10. That was a hard one due to driver issues with my Bluetooth card at the time.

Kubuntu 22.04 on my laptop & Ubuntu Mate 22.04 on my desktop/server.

Kubuntu

Primary PC, runs windows 10. I have lots of various software development related programs which just works here. They don't work as well on linux.

All of my servers (Except blue iris), are running linux. Mostly ubuntu.

The other various gaming PCs around the house are running Ubuntu too. (Kubuntu to be more specific)

macOS Ventura on the Studio and the MBP work machines and Windows 11 Pro on the living room gaming tower.

Arch right now. Probably going to give NixOS a try in the near future though.

I use Debian 12 on my main pc, and on my laptop I use a OS that is based on Debian

Windows 11, because it was preinstalled and i just surf the web and stream from Netflix, Disney, Prime etc.