Antibiotics will likely become obsolete when you can target bacteria without the bystander side effects they have on our cells. They are the perfect antibacterial smart weapon really.
https://medcitynews.com/2020/01/adaptive-phage-gets-10-from-...
Antibiotics will continue to be effective precisely because they are broad spectrum. A doctor can hit you with an antibiotic before they know exactly what you have.
I am always happy to see new tools in medicine. However, I suspect phages are most going to be used initially in persistent, chronic, antibiotic resistant infections where everything else has failed.
I still think in the cases you describe that they could stand to replace e.g. Vancomycin - BEFORE that fails. The side effect profile for that drug is horrendous: GI bleed, neuro/sensory damage, liver damage, retinal damage etc..
It seems like a blend of phages with slightly varied activity could also reproduce the broad spectrum effect, and CRISPR is going to make that pretty easy I think.
These may be the first in the USA. They were mainline therapy for certain indications in the USSR since the 1930s are are still in use in the former USSR today.