Yes, Denuvo has recurring costs to the developer, it's not a one time payment.
In the case of Lies of P though, the developers accidentally included a debug build .exe without Denuvo in an update, only afterwards was it actually removed entirely because there was no point in including it anymore.
It's always funny when they go to the expense of licensing Denuvo but then accidentally release a DRM-free version one way or another. The other classic blunder is to release a free demo version with an executable that is complete enough to play the data packages from the full version of the game if they are swapped in. That's what "demo bypass" means in the Reddit table.
My (unnamed) favorite was an indie game that you could download with no payment required, but that would prompt you for a key at installation time. If you had 7zip installed, you could just hit context menu on it, do "extract all", click on <game name>.exe and there it was, the full version with no key required.
