Is there any indication that the organisms we have "stolen" antibiotic molecules from might become themselves suffer disruption from bacteria that they can no longer kill? Fungi are involved in many symbiotic relationships that we indirectly depend on, for example the fixation of nitrogen for plant growth.

One imagines a future in which we have a dwindling supply of biodiversity to 'sacrifice' in order to keep ourselves safe from bacterial onslaught.

Not unlike oil -- millions of years to produce, but destroyed in a few generations of exponential human growth.