I blame, in large part, the people whose apparent timidity kept the vaccines away from kids under 18, up to 11 months after they were available initially for the oldest people.  
I'm not saying there shouldn't have been SOME delay, in part because older people needed it more.
But keeping that large group unvaccinated meant that they represented a pool of potential infection that needed to be dealt with, perhaps as early as June, when the availability of the vaccine exceeded the demand.

On Tue, Nov 30, 2021 at 8:52 AM, professor rat
<pro2rat@yahoo.com.au> wrote:
65 million Americans who could be vaccinated, who are not, and that is more than enough human wood for this coronavirus forest fire to burn," warns virus expert Michael Osterholm. "And so what we’ve seen happen throughout the world, where basically we don’t get a large proportion of our population vaccinated, we see these surges, some countries are now in their fifth surge, where cases go up and they come down.

https://www.eatthis.com/news-people-covid-first-symtpoms/