re: DRM, there was statistically significant research 10 years ago that DRM / anti-piracy did nothing to affect actual piracy rates, and sales were unaffected largely either way. Most of the money companies spend on anti-piracy stuff is 100% loss. No study I've seen in more recent years shows that has changed - if anything, it's actually even more accurate.
The reason Denuvo etc. still exist is because they are 3rd party companies selling themselves to higher-ups at companies that go with their gut, rather than statistics. It's not usually a significant cost for the bigger companies anyway, but it's still accurate that it does nothing in the long run but inconvenience some legitimate consumers and cost the publisher more money. Just because a big company does something doesn't mean it's the right call. Managers are just people and many of them have little respect for actual research, that is true in my IT company as well, our managers implement and enforce a ton of rules that hinder productivity because they feel like it helps instead.