[1] https://www.usatoday.com/story/news/nation/2020/03/24/covid-...
A secondary point perhaps is that some locations did not have lockdowns or masks for the most part and still have low vaccine numbers. Some locations may have shut down schools at the beginning of 2020 but decided that even masks in schools were a step too far by August 2020. The US response varied wildly depending on location.
The current version is the "Pandemic is Over Act", H.R. 382.[1] This is the "declare a victory and go home" approach.
There's progress in nasal spray vaccines, but they're not really ready yet. There's one that that works in monkeys.[2] Human Phase I testing is starting. China and India have approved nasal vaccines.[3] Effectiveness is maybe 50%. Too soon to tell how fast immunity falls off. The US government is not funding work in this area.[4]
If an effective nasal spray vaccine is developed, even if it has a short immunity period, that could work. It might mean quarterly sprays. (COVID-19 antibody levels seem to drop off after about 90 days, which is why people get COVID multiple times.)
[1] https://www.congress.gov/bill/118th-congress/house-bill/382
[2] https://www.niaid.nih.gov/news-events/covid-nasal-vaccines