> Here is an example where Harvard Stem Cell Institute discusses mRNA therapy as gene therapy: https://hsci.harvard.edu/translation/what-are-drugs-4-gene-t...

And the very next paragraph (in its heading, no less) makes it clear that RNA therapies and gene therapies are distinct, i.e. that RNA therapies are not (necessarily) gene therapies.

The Wikipedia article you cite doesn’t mention mRNA vaccines. The single mention of “mRNA payloads” does not necessarily refer to vaccines (there are other RNA therapies, and some of these might be gene therapies, although I don’t think they are) — but even if it did the sentence’s inclusion in this article is debatable at the very least.

Fundamentally, gene therapies always work by modifying the host genome. mRNA vaccines don’t do this (nor do any other RNA therapy approaches that I’m aware of).