I don't think it quite works like that - human reaction would affect the transmission of both the original 'bad' variant, and a hypothetical 'good' variant equa

I don't think it quite works like that - human reaction would affect the transmission of both the original 'bad' variant, and a hypothetical 'good' variant equally. It wouldn't induce a selection pressure favouring one over the other. Furthermore, even with ICUs overflowing, a large segment of the population considers it 'just the flu' - and likely still would even if it became more virulent. After all, their assessment is based on ideology, party affiliation etc rather more than cold facts.