[oezi]

But mRNA technology is not a gene therapy.

As an analogy:

mRNA technology is NOT like sending a saboteur into a factory to change the blue prints / designs / masters records (=genes) of the factory.

Rather it is like dropping a bunch work instructions (RNA snippets) over the factory and have some workers (cells) pick them up and build the things described there-in.

mRNA tech isn't the same as CRISPR.

The worst that could happen is that a work instruction that we inject becomes self-replicating (a virus), but because it can't replicate to begin with it there is no way that it mutates to gain such an ability.