Hmm, not really sure this is a reason to hate Pixar.

"But they also looked a little too much like the unicycle from the animated short film Red's Dream. At least, that's what Pixar thought."

I think it look exactly like bike from Red's Dream, which was released in 1987 so any similarities might not be accidental. Also, 1994 is around the time they were ramping up for their first movie release and an IPO so I'm sure they had to "fix this" incase there were any questions.