When we have 100% coverage of all age groups.. we will still have covid hospitalizations. We will still have covid spread. We may still even sometimes need to wear masks and have lockdowns.
You should still get vaccinated and get boosters, but no vaccination rate is going to make this go away anymore than the flu shot has eliminated the flu.
The difference is that the load on hospitals will be far lower, which means better care for people that are hospitalized for covid, and people who need to be in the hospitals for other reasons.
Unfortunately, this may have been true in 2020, but at this point the rate of SNPs (mutations) creating VoCs (variants of concern), plus the break-through infection rate, strongly suggest that no level of herd immunity (even 100%) will lead to suppression. At this point we'd all be better off focusing on ways to slow the spread.