Ryzen Threadripper/Alienware - worth the money to run Photoshop?

Four to six cores is what Photoshop can effectively use. Anything above that is quickly diminishing returns.

You don't want a traditional SATA SSD. You want one of the new PCIe M.2 (aka NVMe) SSDs. This is a small card that plugs directly into the mainboard - but obviously make sure the mainboard supports it. These M.2 SSDs are ridiculously fast, and the significance of that is the Photoshop scratch disk. With scratch disk on one of these, RAM is no longer as critical to Photoshop as it once was. The scratch disk isn't a noticeable bottleneck any more.

The video card is the wild, eh... card here. My policy is to avoid the gaming cards - the drivers are optimized for gaming and full of bugs in Photoshop. It's totally unpredictable. A much safer bet is to go for a card targeted at CAD, 3D and graphics - like a NVidia Quadro. The Quadros have their own dedicated drivers.

The entry level Quadros are no more expensive than a NVidia GeForce 1060.

There are companies that make kit optimised for design rather than gaming. There are diffferences, such as multiple hard drives perhaps (though SSD could change that). Different preferred GPUs. And surely if money is no object 32GB is far too little RAM: Photoshop can use RAM effectively for large images. But it depends on your work mix.

Moving to Photoshop​