I don't know, this sounds just like the failed launch of the Galaxy Nexus back in 2011 that had a Verizon exclusive. How'd that do for the popularity of the Nexus brand ? I don't think anyone even knew that phone was out, except us diehard nerds. And if you weren't on Verizon, you had to pay full flagship retail pricing for the phone.
And of all the major U.S. carriers, Verizon is the worst, just total tool bag Nazi company, why would Google think another Nexus device would be good to be exclusively on Verizon ? Whereas T-Mobile is the friendliest carriers to developers and cool with unlocked bootloaders, and they don't put a ton of crapware on their phones. Actually T-Mobile has the longest relationship with Nexus phones, they sold and stocked the Nexus-One, the Nexus-S, the Nexus 4, and the Nexus 6. No other carrier supported Nexus phones like T-Mobile.