You are exhibiting tunnel vision.
When injecting into the muscle it is possible to get some of the dose into a small vein.
Only to someone who is focused on pushing a point of view thinks that it is irrelevant that many things can enter breast milk. It is relevant because it is wrong to be dogmatic ahead of targeted research in an area where there is incomplete understanding and a poor ability to predict.
Your statements are the kind that are given to the public, incomplete in the details and simplified to be used for general understanding. These kind of statements are like those given on food pyramids, which were constantly revised as our understanding evolved. The food pyramids were not only wrong but caused great harm. Humility is an important characteristic for a scientist as is caution in theorizing ahead of the data.
This is interesting. I have no idea if it is true or not, but
https://www.breastfeedingbasics.com/articles/drugs-and-breastfeeding
IM injections, drugs transfer quickly into the milk because the muscles have so many blood vessels, so the drug enters the bloodstream quickly.
Actually, I covered that in point #2. The body is VERY efficient at destroying foreign nucleic acids and proteins. Even if a miniscule amount of the vaccine mRNA entered the blood, it's unlikely that it would reach the breast milk. And if it did, so what? The baby's body also destroys foreign proteins and nucleic acids. Besides, assuming that enough mRNA could possibly survive to enter the breast milk to be consumed by the baby and survive the digestive process in a large enough quantity to cause an immune response, is inducing immunity against Covid-19 in a baby really a BAD thing?
Your statements are the kind that are given to the public, incomplete in the details and simplified to be used for general understanding.
Of course they are simplified. Very few FReepers have the benefit of a PhD in biochemistry and molecular biology that I have. If I were to use the same level of detail in my posts that I would use in a scientific publication, I'd quickly lose all but one or two people in the FReeper audience. I'm not trying to show off that I'm highly educated and have a large vocabulary here. Rather, I am trying to communicate complicated concepts in a way that is accessible to my audience.
When I have written documents on scientific matters intended for Congress to read, I was told to write them at a 6th grade level so that members of Congress could understand. At least for FR, I write at a level above what I would write for Congress.