That is true, but treatment during the infection will be big win for them. And not everyone one want to get vaccinated, there are countries in Europe with very low % vaccines and IMO never going to reach herd immunity.
It is just a matter of time, there's still shortage with the vaccine supplies worldwide and that's why some countries are not yet into herd immunity.
Currently, we have to bear with the situation and like what was said, the vaccines are doing well and it has lessened the fatality that those places that has their majority citizens to be vaccinated.