2000 was the year of Windows 2000 and Windows ME. Did you ever use those in a professional capacity at the time? I think if you did, you wouldn't say you're a big Linux fan _and_ advice a company to use Windows. Or maybe we simply have different definitions of what a "fan" means.
I was more thinking in terms of what you could readily hire programmers for around that time. Definitely did not mean to imply that Windows was the actual better tech stack, just that for various business reasons going with Microsoft may well have been a better choice.
Though in regard to tech stacks, I also thought X.com might've been using .NET and (if that had been the case) then to my mind it was the better option, compared to what many people were using for scrappy Linux web backends in that era – PHP (which I say as someone who wrote his first web backend in PHP). But after looking up the timelines, I realize that this wasn't the case. Musk was replaced as CEO in 2000 and .NET was released in 2002.