I've used plastic containers to heat food in the microwave for years. I bet plenty of people routinely use plastic containers that are safe for the microwave, even if only to cover the plate of food they might be heating. But no matter what the packaging tells you, experts still believe that using plastic in the microwave is bad for your health.
I've always paid attention to using plastic containers that are deemed safe to microwave. I never stopped considering what that safety meant. It's not about human health.