I’ve read Linus’s book several years ago, and based on that flimsy knowledge on back of my head, I don’t think Linus was really competing with anyone at the time. Hurd was around, but it’s still coming soon™ to widespread use and things with AT&T and BSD were “a bit” complex at the time.
BSD obviously has brought a ton of stuff on the table which Linux greatly benefited from and their stance on FOSS shouldn’t go without appreciation, but assuming my history knowledge isn’t too badly flawed, BSD and Linux weren’t straight competitors, but they started to gain traction (regardless of a lot longer history with BSD) around the same time and they grew stronger together instead of competing with eachother.
A ton of us owes our current corporate lifes to the people who built the stepping stones before us, and Linus is no different. Obviously I personally owe Linus a ton for enabling my current status at the office, but the whole thing wouldn’t been possible without people coming before him. RMS and GNU movement plays a big part of that, but equally big part is played by a ton of other people.
I’m not an expert by any stretch on history of Linux/Unix, but I’m glad that the people preceding my career did what they did. Covering all the bases on the topic would require a ton more than I can spit out on a platform like this, I’m just happy that we have the FOSS movement at all instead of everything being a walled garden today.