I've made an observation about ALVINNN that, unlike previous incarnations of the Chipmunks, this one is clearly set within its own, self-contained universe, whereas previous ones were actually more grounded in reality.
By that, I mean, in previous incarnations, the Chipmunks actually mingled with, or at the very least acknowledged the existence of actual, real-life celebrities: in the 60s, they put out an entire Beatles cover album; in the 80s, they had a crossover with Mr. T, sang with Dolly Parton, Alvin danced with Michael Jackson, Eleanor discussed Cher's love life; that Rockin' Through the Decades special had all kinds of celebrity guests; and even that "Chat with Alvin" track mentions Alvin was interviewing Ross only because others like Tom Cruise, Cindy Crawford, Jim Carrey, Alanis Morrissette, and whoever else were unavailable. Not to mention there was also that episode about the Berlin Wall!
ALVINNN, on the other hand, has generally avoided all of that. In fact, they've sort of gone the SST route in using generic, parody stand-in names for actual celebrities instead (such as "Lady Rah-Rah" mentioned in passing on occasion). Though, there was that one occasion where Alvin and Brittany were competing against each other to win an opportunity to meet Princess Kate - that may or may not count as an exception, but it's never explicitly explained if it's the actual Duchess of Cambridge, or an in-universe princess who happens to be named Kate.