Your perception has a lot of validity, but there is much more that you may be unaware of. I met Steve Ballmer with his kids while he was CEO of Microsoft and Paul Allen used to come to a dance that my wife and I used to go to every year. They were both sociable and approachable but neither seemed like super geniuses. I also have known quite a few other people who worked for Microsoft in earlier days and made a lot of money... they obviously were smart people but one felt like their success had more to do with them being at the right place at the right time.
My great uncle started out with nothing in the 1920s but became a millionaire by the 1940s and 1950s back when that still meant something... he also was very bright but didn't seem super intelligent.
Timing, having some good ideas and knowing how to capitalize on them is how almost all of these big tech billionaires have come out on top. The true innovators usually are not the ones who have made fortunes.
Microsoft has come up with some good products other than Windows. I think you are forgetting that Office dominates that segment of the market as well, despite many good open-source products that are perfectly adequate for most people. They are also the quiet leader in the AI marketplace; they spent over $11 Billion developing ChatGP and $Billions more on GitHub Copilot and other AI projects.
Yes, Microsoft has had some market failures with phones and tablets... but they have their tentacles in so many other projects that most people just are not aware of like Azure and other cloud-based projects. And it goes on and on. They are a behemoth in many ways that fly under the radar.
All of the big tech giants have well publicized failures, because they all are hoping to use their unimaginable fortunes to dominate the next big thing. The problem is that none of them really have the United States or even the world's best interests in mind and they use their influence in ways that are bad for humanity. This is because power corrupts and those with power and influence always seem to let it go to their heads. The leadership at Microsoft is certainly no exception.
I didn't forget about it. The success of those products has little do do with anything but the same inertia that keeps MS-Windows on almost every corporate desktop. I've been using openoffice for years and no one at work knows or cares. The other thing is "exchange" and "active directory" which most businesses wouldn't know what to do without because they have people in IT who literally don't know anything else. Outside of the office though, most people do =not= use outlook for their personal email, because it is such a fragile product.
I have a spreadsheet that I used to update annually on my website that deals with the national debt going back to 1791, that excel still can't correctly interpret because the years confuse the software.Open/Libre Office has been able to handle it all along, but Microsoft simply doesn't care enough to make a decent product. I have hated that company for decades now, for good reason.