Gates attended Lakeside school, a private school that had a computer. Gates and Allen took advantage of that to learn how to program. None of the other students did.
Then they went to Harvard, which also had a computer available to students. I expect most universities at the time did. They took advantage of it to develop a Basic interpreter. Nobody else at Harvard did, nor did any other students in the country who had access. Basics were developed for other processors by other people.
IBM came to Gates to get a DOS for their PC. Gates didn't have one, and sent them to Gary Kildall. Kildall failed to recognize the opportunity, and sent them back to Gates. Gates didn't have to be presented with opportunity twice. He still didn't have a DOS, but figured he could get one. He bought one from Tim Patterson for $50,000. Patterson also failed to notice the opportunity.
And the rest, as they say, is history. What is clear is that Gates/Allen were hardly the only one who had opportunity, but they were the only ones to recognize the opportunity. Nobody was cheated. Money was not extracted from anybody. It was all fair deals.
A couple years later, Steve Jobs also saw opportunity where nobody else did. We all know the result. Woz wrote a Basic without access to any other computer, showing this was hardly impossible.
I also had those opportunities, but I FAILED TO RECOGNIZE them, and so missed out on being a multi-billionaire. I was not rooked out of opportunity. Nobody oppressed me. I'm not angry about it. I, and tens of thousands of others, simply failed to see the opportunity, and/or lacked the guts to take the risk and to the hard work needed to take advantage of it.
I also competed straight up with Microsoft in the 1980s, and was fairly successful at it. I recognized the opportunity that C++ offered (finally I bet on the right horse!), and capitalized on it, doing very well by having the only native C++ compiler that worked on DOS. Until Microsoft and Borland belatedly got into that market, and yet I still prospered with it.
Microsoft and Borland never tried to bury me with any tactics, they eventually outcompeted me. Microsoft did try to buy me out at one point, but I declined as I thought the offer was too low. I turned out to be right on that one, too. Borland tried to hire me, too, but the offer was insufficient.
Microsoft was a tough competitor, sure, and if you wanted to compete with them you had to bring your A game. I've seen a lot of their competitors frankly whine about it, when they were making obvious missteps that were the actual architect of their demise.
At no point did Microsoft ever force anyone to work for them or force anyone to buy their products.