Yes, but what about the HTC and Samsung phones? Are you saying that Verizon has a different attitude about rooting just with Moto?
Why do you think the Nexus never was produced with CDMA compatibility for Sprint or VZW? They have the same attitude, it's just that Verizon and Moto have gotten particularly close in the bed. Like AT&T and Apple. Fortunately for us, HTC and Samsung are plenty big and sell so much around the world they don't have to bend over quite as far.
"Dear HTC,
We at Verizon/Sprint would like you to build us a phone, with similar specs to the Nexus One that does not run stock Android. We want you to install a bunch of non-removable bloatware. We do not want root access readily available.
You will do this because without us, you would miss out on a very sizeable consumer base."
The result was HTC built the phones and didn't provide root, but they didn't lock it down as hard as Moto either. Verizon gets Moto flagship phones exclusively here in the states. You don't see a Milestone being released on AT&T, they got a Backflop.
VZW and all the other carriers do not want customers to have root access for a number of reasons. Some of the larger ones would be WiFi tethering that they have decided to charge an additional $30 a month for. They also do not want to replace a ton of phones for their customers who have no business messing with root, but would if it was readily available.
I'm sure there are a plethora of reasons, but the over-arching reason is money. They can save money and even make more by not providing or even making root access difficult.
With all that said, I have every confidence that even if root is removed by the OTA 2.2 update for the Droid X, we will have root again very shortly after release. It took just under a week the first time around with the brand new device and UI. The Droid 2 with 2.2, very similar in hardware and firmware to the X, was rooted very quickly as well.
Root is very achievable. The only thing that has significantly slowed our hacker friends has been this bootloader lock. I however, will put my money on the hackers. In my opinion, they are like novacaine. It always works, just give it time.