Because the comment seems to ignore the context here. And the context is one where there are some concerns and so
the Food and Drug Administration asks vaccine producers to enroll more children in their vaccine trials. So as to clarify something they dont know. A commendable intention
if you ask me but I prefer to phrase it as in:
"We have something that might cause heart inflammation in children...Might be true or not. We would like to find out more as we have seen a few cases...Would you mind send your toddler in Monday morning please? We are going to give him this product"
My twins were born three months early, and we enrolled them in several studies during their NICU stay. Several came with potential but limited risks, either of side effects or a treatment regimen that might be somewhat less optimal (one was exploring different frequency of bilirubin lighting, for example).
We did so in part because my kids benefited from other people making that same decision years ago - to participate in clinical trials that might benefit future children like mine.
"We have something that might cause heart inflammation in children...Might be true or not. We would like to find out more as we have seen a few cases...Would you mind send your toddler in Monday morning please? We are going to give him this product"