Technically I used windows 3.1 at times in DOS and OS/2 for some specific piece of software, but it was never what I primarily used and I don’t consider Windows 3.1 a proper operating system, it’s just a desktop environment.
Not sure exactly when, but I know by 2000 I was fully on board the Linux train.
Started using Linux in the days of floppy boot and root diskettes. Lived through the days of hand-crafted SLIP scripts for dial up internet. The days of needing to pay for working sound drivers. Manually calculating modelines in Xfree86.
I have primarily used Windows at work, probably been 99% windows and 1% Unix/Linux. I have had windows laptops and virtual machines for certain specific use cases but it has never been my main.