Listening to it now...
D...C....G, repeat ad nauseum....
It may land on the G, but no, it's in D.
I can see why it sounds that way, especially when you break it down as V IV I, but the I sounds like a half-cadence instead of a final cadence...
So it really is a I-VII-IV progression. It's been a while since I took theory, but that VII may be a secondary dominant instead of a VII chord....If my fading theory knowledge is correct, that would make it a I-V/IV (5 of 4)-IV progression.
And that explains why it feels as if he "lands" on the G chord.
Regardless, it's D-C-G ad nauseum. Call it whatever numbers you like, those don't change. And it's a lot of fun!