While phage therapy is promising, the difficulty is that phages are very strain or species specific. So when you have someone with an infection you need to precisely characterize what the bacterium is and identify an appropriate phage against that strain. This could be a few days of work. Whereas antibiotics have a much wider spectrum of action so you don't need to have much information before starting treatment. So phages are just much less practical in most situations but are promising in some specific instances.

Hi,

Publications on the application of phages and phage-derived proteins for addressing bacterial infections and bacterial resistance to antibiotics (particularly those of multidrug-resistant bacteria), indicate promise for the prospect of phage therapy as either an alternative or a supplement to antibiotics. However, discrepancies in recent findings on the immunomodulatory effects, the host range, and the potential for horizontal gene transfer indicate that we need a better understanding of the interaction between phage, microbiome, and Human physiology before implementing phage therapy.

Further reading:

Golkar Z, Bagasra O, Pace DG (2014) Bacteriophage therapy: a potential solution for the antibiotic resistance crisis. J Infect Dev Ctries 8:129-136. doi: 10.3855/jidc.3573

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and:

Aishat AF, Manga SB, Bioku RJ, Abdulkadir B. An Overview on the Application of Bacteriophage Therapy in Combating Antibiotics Resistance: A Review. 2021.

https://www.umyu.edu.ng/ujmr/ujmr_1_6_june_2021/UJMR%20015%20ELEYELE%20AISHAT.pdf

For common strain that is antibiotic sensitive, the broad spectrum of antibiotic might benefit more in spite of the faster treatment and relief. For whom that is urgent for bacteria culture methods can almost always find resistant strain, perhaps in this case bacteriophage may have its advantage, not only for the incurable one but also the strong side effect of last-line antibiotic may cause. But I don't know if resistance strain may cause different preference of the bacteriophage from original strain.

Im not sure there are enough studies on the use of lytic phages in vivo, yes in vitro, it sounds promising but in vivo, things are completely different.

Have a look at the following RG links for insights.

Article Bacteriophage – A Promising Alternative Measure for Bacteria...

Article Bacteriophages as Alternatives to Antibiotics in Clinical Care

Article Phage therapy: An alternative to antibiotics in the age of m...

The threat of antibiotic-resistant bacteria is pushing researchers to study other viable options. Bacteriophages, an old discovery widely disregarded after the discovery of antibiotics, are now being re-evaluated by ASU researchers. Phage therapy is the therapeutic use of bacteriophages as a treatment for bacterial infections. Each phage is different from the next. Researchers are currently trying to alter phages, and the next step would be to engineer phages. In order to fight bacteria, they must be engineered to fight different kinds of diseases for maximum effectiveness. At the moment, phage therapy is a mixture of different phages.

https://www.statepress.com/article/2020/02/spmagazine-bacteriophages-a-possible-alternative-to-antibiotics

There is a huge amount of evidence showing the importance and limitations of phage therapy. From the hundred years of clinical phage therapy use in Georgia to the recent clinical trials and magistral phage use in Belgium, I would say that phage use will be vital in the near future to mitigate AMR problems.

The personalized approach needed because of host-range ties well with the trend of personalized medicine, while the low cost of phage use allied to positive gains in reduced morbidity/mortality related to bacterial diseases goes well with public health systems. Besides, it is important to keep in mind that phages are not an alternative to antibiotics: they are an additional antibacterial measured, to be used in certain cases or even together with other approaches.

So, answering your question, my thoughts as someone interest in phage therapy for a while is that phage use reemergence has a bright future ahead and will solve many problems.

The incredible increase in the number of MDR bacteria world wide due to the uncontrollable use of antibiotics makes the phage therapy to solve this issue is promising future line of research. Also great efforts are necessary to overcome the limitations face the phage therapy such as narrow host range of phages in comparison to antibiotics, forms can be use to prepare it and possible molecular alterations which enables phages to combat wide range of MDR bacteria.