It's not a bomb where any failure to keep it off the planes is catastrophic. They can afford to have some people defying the ban.
How many people are going to actually read these articles to know which models are affected? How many people are going to remember the articles when it's time for them to go to the airport? How many people are simply going to ignore the rule because their MBP is their primary computer and would rather not go without it?
Can they afford to have some people or most people defying the ban? Because as it stands, it's impossible to tell how many people are just going to voluntarily follow a rule with (close to) zero enforcement....unless they actually enforce it
In-flight fires are some of the deadliest issues one mzy encounter. They can indeed be catastrophic.