Compliance can definitely be a challenge with pharma in pill form, but even with a modest amount of effort, it would radically reduce transmission throughout a population as those who are able to adhere to the dosage schedule would act as a firebreak in the greater population. Like those who are vaccinated against high transmission communicable diseases.

The UK is on track to eliminate HIV transmission within the decade [1] [2] assuming PrEP use within and near high risk populations. So, to answer your question ("is everyone going to take PrEP all of the time?"), that seems like a reasonable solution until a vaccine is approved for prevention and a CRISPR protocol is developed for therapy in the already infected. It may even take some time for HIV production to ramp, making prEP even more important so the at risk don't get complacent and an unnecessary bump in infections occurs.

(it's important to note that kidney function should be monitored in those on PrEP)

[1] https://www.aidsmap.com/news/nov-2017/uk-moving-towards-elim...

[2] https://www.medicalnewstoday.com/articles/how-likely-is-engl...

There are long-acting (e.g. 8 weeks) injectable versions that are outperforming[1] the daily pill so that approach shows some promise. Not that anybody enjoys injections…

[1] https://www.hiv.gov/blog/long-acting-injectable-form-hiv-pre...

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