I say this as an 883 Pro owner, the newer Nomad should be substantially better but I haven’t seen any real documentation of it yet so I can’t say for sure.
It can be done but you need to think about tool length, MRR and whether you want it to be possible or whether you want it to be easy:
Tool length: You’re limited in the depth you can reach by the distance from the spindle nose to the end of the tool (stickout). You really want to minimize stickout, especially on the Nomad, as the higher it is, the more leverage the endmill has against the machine. I generally try to keep stickout <15mm but I’ve gone as far as ~30mm when I’ve had to. This means some 2in thick parts will be possible but you’ll almost certainly have to machine it on multiple sides and some geometry may not be possible. You’ll need to go out of your way to find tools that will reach this far. The Shapeoko also has this constraint but you have the option of going for larger tools and larger spindles which can deal with the increased stickout better (I think, I don’t own a Shapeoko).
MRR: The MRR of the Nomad in Aluminium with recommended feeds and speeds is 0.16cm³/min, so if, for example, you wanted to make a 2in deep, 1in diameter hole in some stock, you’d be removing 26.4cm³, so you should expect it to take 165 minutes, or nearly 3 hours. The new Nomad should be able to cut that in half and these feeds and speeds are extremely conservative, so you can bring that time down with some effort. I think basically all the options for the Shapeoko can blow the Nomad out of the water.
Ease: The Nomad is very much not a machine for removing oodles of metal. It’s a machine for moderately small pieces or work with soft materials like plastics. If your intention is to frequently machine large metal parts and you don’t have stringent requirements on accuracy, you’ll probably be happier with a Shapeoko.
I’ll also add that I feel like Carbide 3D support treats metals on the Nomad like a bit of an edge-case. They won’t help you at all with feeds and speeds beyond pointing you to the aforelinked super-conservative recommendations. They won’t help with finding tools that work well or anything like that, that’s up to you and the community (and the community is fantastic).
The Nomad is also somewhat ill-equipped for dealing with chips. The official recommendation is to frequently clean the machine yourself or to come up with your own solution.
I don’t want to discourage you too much, the Nomad can mill metals for sure, I just wanted to tell you the stuff I wish I’d heard when I was making the same decision you are.