Such collaboration could improve the productivity the same way that MAME did for the arcade emulation: each machine maintainer can focus only on the specifics that machine, while the shared parts (CPU, interrupt chips, host OS interfacing, etc) would evolve from a shared codebase.
DOSBox-X already has support for the PC-AT, PC-98 and DOS-V, and is looking for someone to implement FM-Towns support.
Such collaboration could improve the productivity the same way that MAME did for the arcade emulation: each machine maintainer can focus only on the specifics that machine, while the shared parts (CPU, interrupt chips, host OS interfacing, etc) would evolve from a shared codebase.