This alone does not show what you think it shows. Just so we're clear on the math:

Suppose total population: 1000 individuals
60% get vaccinated: 600 vaccinated individuals
40% unvaccinated: 400 unvaccinated individuals

For the sake of simplicity (as it doesn't affect the answer), suppose all 1000 individuals eventually get COVID once during the next wave.

5% get hospitalized: 50 hospitalized patients

If vaccines are useless (but not harmful), we would expect an equal % from both groups to get admitted i.e. 5% of each group so that

5% of 600 vaccinated + 5% of 400 vaccinated
= 30 + 20
= 50

You can easily see that the percent of hospitalizations from the vaccinated group will be 60%:

30/50 = 60%

Hence the fact that 60% of hospitalizations (including eventual deaths) are from the vaccines is a consequence of the percent of the population that gets vaccinated and vaccine efficacy (here assumed useless). If % hospitalized is equal for both groups, it shows vaccines are useless but not harmful. If higher for vaccinated group, it shows vaccines are harmful. If lower, it shows vaccines are effective.

So we need to see what % of the population they assumed would get vaccinated to understand how confident they are of the vaccines.

Note: This example only considers efficacy against hospitalizations as a metric. To truly evaluate the vaccines costs and benefits, we should include other possible things like long term damages, damages resulting in non-COVID related hospitalization etc.