Back in my CompUSA days (2005-2008) I remember using "completely wireless" as a selling point for the iMac. Back then wireless networking wasn't as prevalent and a wireless keyboard & mouse weren't standard, but once you remove the cables for networking, mouse and keyboard the only cord coming out of your computer was power, and that's really nice from a minimalist standpoint.
These days Apple includes a wireless keyboard & mouse as standard, most printers come with wireless connectivity on-board and network attached storage, while not widely adopted, is a great solution as well, so this dream is more attainable than ever.
If you've got the cash to throw around, you could always pair the iMac with two Homepods and use them wirelessly. (I've seen this in a few desk photos, in fact.)
Not an Apple Watch owner I assume?