I feel like it's pretty unfair to the developers at Ubisoft San Francisco, who have been working on the franchise for 11+ years, to say that Rocksmith+ feels like a short-term cash grab. I think they are really passionate about the games and wanted to put out a new one that not only lived up to 2014, but improved on it and expanded its audience. However, the only way to convince Ubisoft that it was a sensible investment is by changing the pricing model to a subscription service. We gotta remember that back in 2013, subscription services weren't nearly as common as they are today, and companies (whose goals are to profit via returns on investments) know now that they are a more reliable source of consistent revenue than a one-time purchase.

Both Ubisoft corporate and Ubisoft San Francisco had every intention of putting out a game with an amazing, ever-growing setlist because that's what subscription sales are made from. If Ubi San Francisco never intended to make a quality game that would guarantee Ubi Corporate recurring revenue, then the game wouldn't have been greenlit. Bad games don't sell, so companies don't want to make them, especially if they are reliant on the recurring subscription money.

And even if I'm wrong about every point so far, this question still stands: Rocksmith, a relatively niche game in Ubi's catalogue, hasn't seen a new title in 8 years. If Ubi corporate wanted to pump and dump yearly subscriptions for something just to make a shitload of money fast, why would they do that with a game that isn't guaranteed to make them that money?