Simple - most of us (and/or our parents) didn't have wheelbarrows full of cash to head to the Apple II dealer with...
Apple II's weren't *that* expensive... at least not in the 1980's. It's true, my family couldn't afford a IIe (though plenty could; my family was lower middle class). But when the IIc came out, that changed things. It was about $500 less than a IIe in 1985 dollars and it included everything; you didn't need to buy any add-ons.
The difference in price between a full C64 or Atari XL system and an Apple IIc with matching monitor was not very much. The initial price of the C64 in 1982 was $595, but that was just for the unit. And while you could theoretically use only the base unit with no drives connected to a TV, most people didn't use them that way in my experience. All my friends who had them also had monitors and disk drives, which would drive the price up over $1,000. An Apple IIc with the matching monitor cost about $1,400 when it was introduced in 1984.
I think price may have hamstrung the II line a bit in the 1970's and very early 80's, but by the mid 80's the price playing field was more level. By that time, though, the 8 bit II was really showing its age and the C64 and Atari computers had a big game library built up that the equivalent Apple ports didn't compare well with. So in that sense, yes, it was too simple of a computer and didn't have the right hardware to make it more of a home/gaming success. But it was successful in other areas where the C64 and Atari models had less, like business and education.
As for the original IBM PC, I also had a friend whose dad had one, but he was more liberal about it. He'd let us into the computer room whenever we wanted and would allow us to do anything on the PC. The only thing he really had that we were interested in was Flight Simulator, though, so that's all we played. But the things I most remember about that experience was the sound and feel of the computer, the sound and feel of the Model F keyboard and the look of the characters on the screen. I mean, it had an actual *font*! The characters on lesser computers, including the Apple II, seemed like they were created solely so you knew what they were. Like, a "K" is shaped like this, so we put a few pixels to make a line here and another there and another there, and that's a "K" and you can read it and that's all that matters.
But the IBM PC had letters with *style*. They didn't just look slapped together only so you'd know what you were typing. They were an actual consistent and stylish font. The whole computer felt like something really high end to me, with all sorts of attention to detail that my Apple II didn't have. (Yes, at that time, IBM felt like a more detail-oriented, high quality product than Apple.) At that time, PC's really *were* extremely expensive, but I understood why and never questioned it. It seemed obvious why they cost so much. Using an Apple II was like driving a Jeep. Using an IBM PC was like driving a Bentley.