Ah, this is doing something dumb/misleading: it's not conditioning the chance of hospitalization on catching covid.
That is, the normal way someone interprets the question "what is the chance you're hospitalized due to covid" is "what is the chance you're hospitalized due to a covid infection", while you're actually asking "what is the chance you, a randomly chosen person, will be hospitalized due to covid [in the next year]". They're conditioning on a time window, and not a case rate.
Another way of looking at their approach is to consider what happens over the lifetime of a person. If you have a .89% chance of being hospitalized due to covid this year, what's the chance over your lifetime? Unless the risk drastically drops, it's something like a 30% chance of being hospitalized over the next 40 years, or for me, very close to a 50% chance of being hospitalized over my entire life.
That is, the normal way someone interprets the question "what is the chance you're hospitalized due to covid" is "what is the chance you're hospitalized due to a covid infection", while you're actually asking "what is the chance you, a randomly chosen person, will be hospitalized due to covid [in the next year]". They're conditioning on a time window, and not a case rate.
Another way of looking at their approach is to consider what happens over the lifetime of a person. If you have a .89% chance of being hospitalized due to covid this year, what's the chance over your lifetime? Unless the risk drastically drops, it's something like a 30% chance of being hospitalized over the next 40 years, or for me, very close to a 50% chance of being hospitalized over my entire life.