Not true for Pfizer and Moderna, they are completely synthetic messenger RNA (mRNA) therapies . . . They are not really vaccines as we understand them, employing a weakened, dead or inactivated infectious agent / pathogen that the body sees and creates various immunities to combat.
That's the biggest difference . . . Regular vaccines create a wide response in the body, cell-mediated immunity and humoral immunity. Humoral immunity relies on quick response, specific components flowing through the plasma, such as antibodies. Cellular immunity is long-lasing, it is the life-long blueprint for the body to react to pathogens. This is commonly referred to as T-cell immunity; it is not controlled by antibodies and is instead mediated directly by immune cells.
Vaccines that employ deactivated virus offer these wide immune responses as does natural immunity.
OTOH, mRNA "vaccines" trick the body to react to an artificial "spike protein" in the shot and create antibodies. Problem is, this isn't the real virus so it only causes a narrow antibody reaction that doesn't really act to kill the entire pathogen.
This is why we are seeing evidence of "leakiness", vaccine resistant mutations in variations, (especially in Delta and now Lamda and Mu) from
antigenic or immune escape. . . . Hence the increased infection rate in "vaccinated" people and their increased carrier potential. The variations aren't the immediate danger, mutations in a variant, especially when we get into the 4th generation, are the danger because the mRNA "vaccines" just aren't agile enough to keep up.
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