I don't think it's an antivaxer argument but if you develop the reasoning it really becomes somewhat controversial. The problem is that vaccines are not comple

I don't think it's an antivaxer argument but if you develop the reasoning it really becomes somewhat controversial. The problem is that vaccines are not completely effective (efficacy goes down with time, is lower against new variants, there are breakthrough infections, etc.) so variant formation is not completely supressed. Everything being equal (given one exposed or even one infected person) you may have less variant formation with vaccines. But when you have more infections you will end up having more variants. That the number of infections would increase as people's behaviour adapted to the lower fatality rate was not unexpected: people take more risks because the prognosis of an infection is not so bad anyway, once infected they may have a mild, undiagnosed evolution and still contribution propagation... And it's no longer an hypothetical scenario. In many European countries there are more infections now than ever before.