Afaik, macOS and Windows (and probably all modern kernels) use something halfway between microkernels and monoliths, I think they call it hybrid kernels. The reason being there's benefits to both approaches, so why not both?
Linux (and the BSDs) have shown that a monolithic kernel can be modular and well-organized.
Mach’s descendants, L4, etc. have shown that if you want decent performance you either have to redefine “microkernel” or you have to put in an incredible amount of work to implement your simple design.