This article shows a comparison between the 2 mRNA vaccines regarding hospitalization rates.
This comparison, showed that the hospitalization rate at the 4 month mark, is 92% for the Moderna vaccine and 77% for the Pfizer vaccine.
The reasons for this could be related to the strength of the dose (Moderna is higher), or the interval between the first and the second dose (Moderna is 4 weeks, Pfizer is 3 weeks). Also we have to keep in mind that more myocarditis has been seen with the Moderna vaccine