This is a tricky one as it's similar to Amiga OS and Be OS where it's obviously so forward thinking but as other comments state that doesn't automatically lead to uptake.
Of a similar ilk, I always felt the MSX base deserved a higher usage rate in the rest of the world, PC engine as a console too. Neither really took off elsewhere.
> obviously so forward thinking but as other comments state that doesn't automatically lead to uptake.
There are numerous examples for that. Plan9 is another interesting one - they wanted to improve on Unix (and did, in many ways), but the software market just wasn’t that enthusiastic about it.
The GUI looks a bit similar at a trivial level, but underneath, BeOS and AmigaOS were both far more mainstream and conventional than TRON.