The relevancy is mostly for the decisions on what status to give people that had it. E.g. do you treat proof of a past infection as equal to vaccinated status? For how long? how do you handle boosters for them? ... (E.g. in here in Germany an infection that's 1-6 months ago is in many ways treated the same as being vaccinated, after 6 months a single booster shot gives vaccinated status (based on results that at that point a booster helps improve immunity). These policies and how to adjust them depend on such results)