Here's some brain sludge: The choice to get a vaccine is “not just about you.”
Using these new mRNA gene therapies (vactherapies) in this instance, at this time was the right thing, IMO..... for the population most at risk, 65y and older. They account for 16% of the US population but 85% of Covid adjacent deaths. Those individuals were not going to contribute to herd immunity and if the vactherapies lessen their hospitalizations and deaths, then that is a positive. I don't know of anyone of import suggesting that these vactherapies should not have been rolled out for the 65y and older crowd (at risk).
Where the problem arises for "it's not just about you" is that to reach herd immunity, individual immunity must be robust and that occurs in the healthy (not at risk) population. It is acknowledged, now, by everyone that breakthrough cases are the norm. The CDC quit tracking breakthroughs in May, why? who knows. But everyone agrees that a health vactherapied person is going to contract Covid but the hope is the vactherapy will lesson the symptoms. So, in every single infection with viruses like this, mutations occur at a high order. Every person who is infected and develops Covid, will have incalculable mutations of the virus happen during their infection. Mutations occur when some mRNA info gets left out when replication occurs in cells. Most of the time this is just a hiccup to that one cellular-specific replication. So, that "mutation" really doesn't mean anything and is just an anomaly that goes unnoticed.
The issue arises when, for whatever reason having to do with the environment of a specific host and given conditions, that mutation begins to take over as the primary infection. As that happens, the viral load based on that mutation grows and then that mutated virus is shed and translated to another host (another person) and then, bam.... a new mutation out in the wild. We don't know the whys or whats of how a mutation outperforms others or the original infection, hence we really can't do anything about it.
What we do know is that in the average healthy person, the body is geared up fighting the infection and going at it hard. It is learning each and every nuance of that infection and "remembering" the fight. Even the mutations should they grow. So, natural immunity in a healthy person tends to be a broadband immunity after a robust infection as the numerous replications have a statistically large number of mutations that the body sees, but is actively learning and fighting in real time.
When we vactherapy a healthy individual with mRNA gene therapies, the body is not seeing this broadband infection and the many mutations within the replication process. When a breakthrough infection happens, yes, the body recognizes and lessens the symptoms of the infection, but those replications are occurring while the body is casually working on that infection in a non-robust infection. The issue is that the mutations can outflank the body's reaction and a "new" mutation can grow and become the primary infection before the body actually recognizes it because it hasn't rallied all the troops just yet. That infection can grow to a viral load that is shed and is resistant to the vactherapy and generating a whole new mutation that is outside the scope of the vactherapy.
The whole mistake here has been using the vactherapy on healthy individuals, telling vactherapied individuals they can just go about their business (maskless if you believe in masks) and not have to worry about quarantine, social distancing, etc UNLESS their breakthrough becomes bad enough to require hospitalization. So, they were a spreader of a new variant while building up this breakthrough and exposing others, even others who had the vactherapy.
While, when a healthy individual gets a robust infection, their body is in full fight mode and is fighting the virus and it's mutants at every turn and learning and remembering how they fought and won. Then, those using those antibodies to help others when infections occur, stops the spread of mutant varieties or, to be accurate, limits them dramatically.
Herd immunity is only going to occur with healthy individuals fighting the virus, using those antibodies to help future infected individuals and limiting the escape of mutations. It will not occur with mRNA therapies as they will not offer "immunity."