toxicTom: It's hard to get some serious numbers on this.
If it was a big success at improving sales they'd have been making a big noise about the amazing sales figures of their latest games - especially if it had translated into the kind of figures that they repeatedly claimed were being lost to piracy prior to Denuvo's success. Plus most of these companies are publicly traded, so if Denuvo's success at stopping piracy had translated into increased sales the breakdowns of their financial data would likely have shown that.
toxicTom: Also we all know DRM is not only about copy protection, but also customer retention and surveillance. If you have to use the client, you might impulsively buy something through it. And they know what you play, for how long, when and how intensive (achievements!). Perfect marketing tool - this data is worth real money.
It's traditionally been more about keeping as much control as possible over what users can do (SecuROM's tagline was even "get maximum control"), but more recently it has branched into customer surveillance and ensuring an audience for marketing DLC/microtransactions/other games/etc.
toxicTom: ^This. But I'm pretty pessimistic concerning that. When Epic opened their store every went "No, not another launcher!" (as before with UPlay and Origin). And then they all registered for the freebies... and then the exclusives...
We'll see... it's one thing for people to grab the freebies, but another for them to actually start spending money there. Unfortunately, "There's a sucker born every minute"...