This was one of the popular games I had to miss the first entry in back in the day due to stores being sold out of it all the time. I was too impatient to mail a money order into a company from a magazine ad then wait probably two to three months to get my game either.
I got into Mario Kart with the N64 release. A friend had a copy and we played it every weekend, his parents would play too. It was fun playing four player. I had an N64 controller LONG before I had a Nintendo 64 console because of this.
I have tried going back to the first to see what the hype was about but as you mentioned, this one's reception is very different depending on when you started playing the franchise.
For me, I just cannot get into the Super Nintendo Mario Kart. I have tried many times but it just doesn't click with me. It is odd because I prefer the SNES version of F-Zero over the later releases so it is not just a graphics bias with me. The gameplay is fundamentally different with Mario Kart.