Some day, perhaps, but the code is MIT license and anyone is welcome to collaborate. (FWIW, @pcgregory turned my fasttracker 2 player into a full fledged tracker: https://wetracker.herokuapp.com/) I'm busy with other projects now; this is something I keep coming back to once in a while, and if I do it'll be to improve the fidelity before I make a pretty frontend...

It still needs accent emulation which is a bit of work, high pass output filter (it's bassier than a real 303 because there's some capacitors between the filter output and the amplifier I'm not emulating), the knob ranges / nonlinearities aren't quite right...

edit: And it also needs the square wave, which is super weird on the 303, as you're aware (yours has a sample for it I think)