If you have a SaaS product that needs 3D rendering on the server, Windows and Linux servers that have a GPU are targeted towards GPGPU and are expensive to rent.
MacPros have two descent AMD FirePro GPUs but much cheaper to rent.
If you are trying to match your production platform then you will use a VM of some sort in Linux anyway. If you are not trying to match your production platform then you can develop just fine on OSX.
MacPros have two descent AMD FirePro GPUs but much cheaper to rent.