I believe Denuvo charges for access to the activation servers. [0]
While the pricing structure has likely changed, for most game companies the long tail end [1] of the sales doesn't justify continuing.
For example, Square-Enix(Final Fantasy, Dragon Quest) removes Denuvo 6 months into a release. For a counter-example, Atlus(makers of Persona/Shin Megami Tensei) are known to never purposely remove the protection.
From a digital historian perspective, I do like the idea of DRM that is just there temporarily to ensure the fat-head of sales before being removed... especially when there's an economic cost spurring companies to not keep it around indefinitely.
The flipside of that is companies not bothering to remove it and ceasing the payments to denuvo effectively making the game not exist anymore until someone is able to crack it, and very few people seem to be able to do so. Not that much of a stretch when you look at the amount of abandonware we have.
Denuvo claims to have a solution to that as well, but to date it hasn't actually shown up in any games. I kind of hope at least one publisher bites just because I'm curious to find out what horrors they've cooked up to make emulation difficult.
There is precedent for that kind of thing, Wii emulation matured early enough that a handful of retail games had code specifically intended to frustrate running them in Dolphin. They abused some details of the real Wiis L1/L2 cache which aren't simulated by Dolphin, and couldn't be without adding an unreasonable amount of overhead.
It could be they are just waiting for the switch 2 to really focus on it. Somebody mentioned how atlus never removes denuvo and also aren't releasing persona 3 for the switch, but will release it for the switch 2.
[0] https://www.techpowerup.com/275158/denuvo-drm-pricing-struct...
[1] https://en.wikipedia.org/wiki/Long_tail?useskin=vector