I was curious about the details, so I looked up The Economist's 2018 annual report. They get 17% of revenue from advertisements, while 60% of revenue comes from subscriptions. Their operating profit is 13% of revenue.
Right, but of course without ads they would save some cost as they wouldn't need people to sell ads, they could get rid of a bunch of ads-related overhead costs etc.
If the operating margin on the ads part of the business is less than ~25%, then they could break even without ads. Of course, breaking even is worse than making 35MM profit each year.
