The company was never large enough or powerful enough to greatly influence the course of computing the way Windows and Intel have been able to and they were relegated to the "We want to be different" crowd.
Everyone has an opinion and as someone that has been around the computer scene and worked with and on most platforms, that's mine.
Well, this may be your opinion, but I'd have to say that the part about Apple not influencing computing is ignoring some real world data. I've been in the computer industry since the early 1980s and, the data just doesn't support your opinion.
Who launched the first commercially successful GUI in 1984, that Microsoft didn't get close to right until the 4th iteration (Windows95)? Apple. Did they create the idea of GUI? Absolutely not. They just created a commercially successful product that the market is still trying to keep up with 25 years later.
Who created the modern laptop design by pushing the keyboard back and inserting a pointing device between palmrests, thereby creating the industrial design standard that every laptop maker has used ever since? Yeah, that would be Apple again. What company released the first commercially available laser printer that, when combined with WYSIWYG display and layout software helped create the entire digital publishing industry? Oh, that would be Apple.
I'm not saying that they got everything right, or even that they're the largest innovator in modern computing, but to say that they were never large enough to influence computing in the way that Microsoft or Intel has is ignoring a lot of real world data. As far as being big enough to be influential, it was actually Apple that was the first computer company to hit $1B in annual sales. That seems like a pretty big influence, especially when no one had ever done a fraction of that sales volume before.
Sure, Sony made some huge advances in thin laptop design, and Intel and IBM's pioneering of smaller and smaller chip die designs have been game-changing. Intel's multicore chips have allowed software developers to take advantages of processing power in ways no one could have predicted 20 years ago. Dell's innovation in "just in time" manufacturing revolutionized the way that computers are assembled and customized, allowing for huge reductions in cost and time to ship. These are just a few examples of innovations that I would call "influential".
All that said, I'm just saying that if you look at the companies that have been influential in modern computing, Apple has to be near the top of that list.