On average, people who lived a century ago had considerably less leisure time than
Why this is right
This points to another difference between then and now, and this difference helps us argue that people back then would do less reading than people nowadays. Sure they had fewer options for amusement, but they also had considerably less leisure time. If you're plowing the fields or working the factory floor for 15 hours a day, then you might only have 30 minutes to read at night, and so you're not really reading more than people nowadays. "Considerably less" has some punch, which is what we want on Strengthen / Weaken / Paradox. This answer by no means proves they did less reading back then, but that's not the job of a correct answer. It weakens by introducing a new factor that works against the author's conclusion. The more leisure time people have, the more they could potentially read for pleasure. The less leisure time people have, the less they can read. By introducing a distinction between then and now that makes it sound like "nowadays, we have much more leisure time", it makes it harder to argue that people back then read much more than we do today.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.