They make silver.I have a 2019 intel iMac and would to upgrade; but with two ports it really puts me off. I also think the two tone colour thing is ugly.
In practice, I find that investing in a USB-C or Thunderbolt dock to be a more viable option than just having two more USB-C ports on the back. Invariably, you're going to need the occasional USB-A or SD card slot. And reaching around the back to plug in a dongle is always a headache.
Don't get me wrong, the 4-port TB/USB-C version is definitely nicer with the ethernet and TouchID trackpad and I get good use out of those. But having half the ports wouldn't really slow me down that much because if you're really going to use it "like a computer", a dock or fully-featured dongle will probably get a lot of use.