I'm judging by the sharp decrease in demand for the vaccine when we have plenty of doses. It's clear the number of people who can't get one is dwindling fast.
The number of older people who are vulnerable and won't get vaccinated is the bigger problem than teens with a sub 1% infection rate. More needs to be done to get those adults vaccinated.
The problem is we don't know the full range of side effects but fatal blood clots may be just one example.