It could happen, but we already have 30% of people with MRSA colonized in their noses. If we develop a new antibiotic that saves thousands or millions of lives,

It could happen, but we already have 30% of people with MRSA colonized in their noses. If we develop a new antibiotic that saves thousands or millions of lives, but the MRSA colonization number climbs to, say, 60%, will that be a net gain? I think so, since in general having MRSA colonized is not problematic, and that number is climbing anyway.