as an anecdotal data point, my wife has a phd in a relevant field. her dissertation involved the lipid nanoparticles used by the pfizer vaccine as a delivery mechanism.
in her words no one really knows how the lipid nanoparticles actually work, and it is much too soon to be forcing this onto the public, and thats just the delivery mechanism. so you have a novel mRNA vaccine, with a novel delivery mechanism, and very little long term safety data. she does not feel like these have been tested to the same standard as other vaccines, we are at the point where if this is mandated for our children we will probably move somewhere they are not.