My reasons:

• You can completely customize linux to your liking. In win it is hard to customize even such a basic thing as keybindings.
• You can fully control what is installed, win had tons of stuff, that cannot be uninstalled.
• Things like proprietary software, telemetry etc. is opt-in, no need to deal with windows spying on you for example
• System is leaner, less bloated (you can fill it with processes if that is what you need ofc)
• Dev environment is a lot more comfy than linux

The biggest downside:

• Gaming is rough around the edge, even though it gets better and better.