Agree this is highly subjective. However, for the average US “bottom”, I find the seats in a Mazda 3 very supportive and comfortable. If you have any trouble bending while getting in and out, an SUV or similar high model would be best. A Mazda 5 has both generous and high seats. It’s really worth a try. You don’t need to spend a fortune to get good seats.
A friend of ours has a rare degenerative disease which makes most bending difficult. They kept their Dodge minivan since it is easy to enter and exit as well as having comfortable seats.
Generally, smaller cars have shorter seats and those are the least comfortable.