Squeenix, or whatever they fancy calling themselves these days, were operatic about not using Denuvo on Final Fantasy XV's PC version. They've since doubled back on those claims. Either way, pirated copies of FFXV for PC are now a thing.
DRM is a fancy acronym for the practice of screwing over players who paid for your game, in order to fight people who were never going to purchase your product in the first place.
We won't pretend to understand the technical side of making Ds do an RM, but there are people with a much better understanding of these matters over on reddit.
They are currently engaged in quite a lively discussion about how long it will take for the industry to realise that Denuvo has become a joke, much like SecuROM or any of their ilk in years past.
This whole fiasco offers PC customers the usual purchasing freedom they are familiar with, but extended beyond the demo and Steam's two-hour refund window. For Square, it is just another in a long string of embarrassments.
Final Fantasy XV has enjoyed overwhelmingly positive feedback from critics and players alike. Just kidding - the PlayStation 4 metacritic score sits at a comfy 81%, with users rating the game around 7.5 on average. Taking review score inflation and the inherent absurdity of scoring a work of art with a two figure number into account, all of it amounts to little more than a startled meh.
No universal acclaim like FFVII, or hushed fanboy praise like FFXIV. Just a band of CYP and 3DM crackers giggling in Italian and Chinese respectively.