Judeling

Couple things:
1.) Basically all PCIe 2.0 motherboards I know don't support booting of PCIe storage, so unless you were going to use it as a spare storage, it wouldn't work.
2.) For the devices that have fully wired x16 slots of PCIe 2.0 (so basically Nehalem and older), you just aren't gonna saturate a full PCIe 4 x4 interface with data throughput in almost anything but benchmarks. 
3.) it would require PCIe switches, which are expensive, and you'll probably end up paying more than your system is worth for a drive and one of these adapters.
 
Basically, it's a very niche product that for 99% of situations makes no sense, so therefore it doesn't exist.

theoretically this could be made possible, but I don't think a product like this exists, because the market segment for users of this product would be so narrow. Of all the PCIe x16 NVMe adapters I've seen, they all incorporate 4 separate NVMe slots instead of adapting one NVMe connection to a single 16x bus

Granted if this was real, I would be tempted to get one for myself

I need a 4k, 32 inch display for creative work. Which means I need the best possible color accuracy. I don't intend to do any gaming on it.
 
I was hoping I could get some recommendations because I'm a little lost and researching monitors has become stressful.
 
32 inches seems big, but I really need the space to get detail in my art. I'd even go bigger if there was a good option. I'm hoping to spend under 500 dollars, but if a monitor is perfect, I'd consider a little more.