Yes, they did sit down and think that through. That's their job. This is not the first epidemic. Public health departments, unlike people on the Internet, actually study the topic.
You might consider sitting down and thinking about who is making these decisions and what their backgrounds are before you pronounce that they didn't take something into account. On what basis are you making that accusation? Do you have any idea what other things went into that decision?
Perhaps they made the wrong choice. But they weren't guessing. And I don't have a lot of respect for your guess about it if you don't even know that much.
When scientists in the U.K. started talking about herd immunity - the only way out of a pandemic - people went nuts and they quickly had to stop using the term and start reassuring more than informing.
Average pandemic is about four years, not much has changed. They just had to keep people going at the time.
Except they accidentally did a real-world experiment and we discovered that people needed to be consoled and not confronted too suddenly with the inevitable
You might consider sitting down and thinking about who is making these decisions and what their backgrounds are before you pronounce that they didn't take something into account. On what basis are you making that accusation? Do you have any idea what other things went into that decision?
Perhaps they made the wrong choice. But they weren't guessing. And I don't have a lot of respect for your guess about it if you don't even know that much.