Again, wrong. Symbian actually scaled "down" from palm sized PC's to phones via Nokia Communicators. What went wrong with Symbian was that it got too messy, and no one alive (literally) being able to do a full clean-up, to modernize it.
But let's be real honest. The only success Linux has had is on Android. The only reason for that success is Googles hard line on cutting off all the bloat. In the embedded world as well as the PC, Linux will work, but is seldom used for anything real. The reason being it is a simplistic bloatware.