Well I don't know about that.
The main limitation I currently see is the web browser.
I was using Dropbox in the Web Positive browser and it was horribly slow, and Youtube also didn't seem to work.
I don't understand what's preventing them from porting Chrome or Firefox, but I'm guessing it's limitations in the BeOS API.
The system itself is built with a fork they have to maintain of GCC 2 & 7 because they have to maintain BeOS compatibility.

But it's impressive how well everything works. Inkscape & GIMP both work well. It plays back 1080p video smoothly.
There's a fair amount of software ported.
It's almost good enough to be a daily driver.