I thought they were in reference to needing a physical phone or device for Google Voice. GV is online, software.
I have, in the last 1yr or so, created a few other GV accounts numbers, one for junk use, and one for my home phone. It never asked me for code.
I just tired to create a new GV on one of my existing Google accounts. It now asks me to verify via text message or phone call. I put in my R.W. number for the “call” option u have to select in the text area. It did not reject my number because not supported, but because already in use on another GV account, so I can t really test it I guess.
Edit: I have never heard of Venmo until this thread. It appears to to be some “Digital Wallet” or otherwise money share service? How would this service be any different than PayPal, Google Wallet, or Square? My bank, Wells Fargo, now uses something called “Zelle” but it appears to just be the same money transfer option pages they had before.