RNA is not a gene and not a replicator, it carries information. It's technically wrong to say it's a gene therapy, but it's murky and I understand anyone who doesn't trust this new technology yet.

But we do have ongoing processes in our cells which take information in RNA and copy it to our genome (DNA). HIV is one example, a virus that takes segments of RNA and inserts them into the genome. We also have endogenous processes which bring RNA segments into our genome. This could mean some children could inherit RNA insertions which their a parent has received from the vaccine. It can mean nothing, it can mean a lot. We don't know, because thanks to the emergency approval of the FDA, this is the real trial phase.