If lots of people have known this for some time, it's an excellent example of the Dunning-Kruger effect.
Or to paraphrase Ronald Reagan, the trouble with some of our friends is not that they're ignorant; it's just that they know so much that isn't so.
The referenced article refers to a presentation by Dr. David Martin (no relation to me),
who is not a medical doctor, but rather a financial analyst, businessman, author and self-help entrepreneur. He appears in the discredited film "Plandemic" and apparently supports anti-vaxxer Robert Kennedy, Jr.
He claims the mRNA vaccines are not vaccines because they do not introduce an antigen, and because they do not prevent infection nor transmission. Rather, he claims, the mRNA vaccines are "gene therapy."
It is true that the mRNA vaccines do not introduce an antigen; rather, they introduce mRNA that instructs the human cells to manufacture the antigen. In other words, new technology to accomplish the same result.
Very few vaccines completely prevent infection and transmission. There is ample data from several countries (not just CDC) to indicate that the mRNA vaccines do prevent infection and transmission, not 100% of the time, but enough to make a significant difference. Further, the mRNA vaccines were developed specifically against the alpha variant of Covid, and are less effective against subsequent variants, which makes medical sense.
Are the mRNA vaccines gene therapy? The accepted definition of "gene therapy" is the treatment of a medical condition by replacing a defective gene with a healthy gene, or introducing a gene with specific disease-fighting ability to replace an existing gene. Either way, the person's genetic material is altered.
Recall that our genes reside in the nucleus of cells. Gene therapy therefore involves introducing new genetic material into the nuclei of cells.
mRNA vaccines to not introduce genes, and do not introduce any material into our cell nuclei. Rather, they provide mRNA into the cytoplasm, providing the cells' existing genetic structure a set of instructions on how to manufacture the antigen, which in the case of Covid is a spike protein. The mRNA does not enter the nucleus, is destroyed over several hours to days, and does not permanently alter the genes within the cell nucleus.