It's often repeated, but this is a silly slogan. It's not either-or. Subscription magazines have ads. There is nothing preventing a business from making money from users and ads, and if anything, a subscription makes it easier to know who your users are, so the ads are more valuable to advertisers.

Some business models require this; most newspapers wouldn't be in business without both subscription and ad sales.

Windows 10 is apparently a case in point: it's not free and it has ads.

Or, they sell both the license and the users by having an install base that has trouble switching. Remember windows 10 ads? https://www.theverge.com/platform/amp/2017/3/17/14956540/mic...