The truth is, perhaps, not so politically correct; but it is simple: The higher the vaccination rates, the more trouble with COVID cases. Israel is a prime example. It became the first country to have a majority of its population vaccinated. Around the same time, it began having a surge of new COVID cases. This information is documented in news reports of that time, such as this one:
Naturally, they try to explain it. But having lived in a landlocked undeveloped country where there were zero vaccinations, and zero cases, and which then had twenty cases but no deaths (they likely had no ventilators, and masks were not even required to enter the one hospital in the country designated for COVID cases--I entered it myself multiple times without), I witnessed that as soon as the vaccines were pushed, a surge in COVID cases happened...which the government attempted to blame on illegal border crossers.
We can look at places where more data exists to do more careful analysis of what is happening. Take Florida, for example.
Florida vaccination rates varied by county, as depicted in the graphic below (SOURCE).
Its case/transmission rate also is known, and varies by county.
See the full, actual report from Florida's department of health HERE.
The images indicate that the highest rates of transmission occur in the counties nearest the half-way point for vaccination--the areas where, mathematically, the greatest numbers of "unvaccinated" would have contact with a vaccinated person.
But keep in mind that none of these statistics are accurate. The CDC does not consider one to be vaccinated until two weeks after the vaccine was administered. This means the statistics are skewed. It could be that the majority of the case transmissions were actually in those recently vaccinated. We simply cannot know because of the way they arbitrarily draw the line.
See the CDC's own statement on the two-week vaccination rule here:
So, if the vaccine induces COVID-like symptoms, which are taken to be COVID, and if the vaccinated are still called unvaccinated for the first two weeks, it stands to reason that the rates of "transmission" will be highest in areas actively administering the vaccine. Japan's lower vaccination rate helps to explain its lower numbers of COVID cases.