> The whole point of mounting solar panels should be to maximize area that is facing the sun.
There are a lot more considerations to get into e.g. in areas with lots of snow verticals are significantly less affected and benefit more from reflection, in summer vertical E/W bifacials have a “double hump” which provides more generation in the morning and evening, verticals take less floor space so you might be able to get extra panels or get panels at all, N/S bifacials have better winter production unless your slanted panels are “detuned” from perfect summer angle (or even better have a tilt mount you can update every few months, but that is not cheap).
There are a lot more considerations to get into e.g. in areas with lots of snow verticals are significantly less affected and benefit more from reflection, in summer vertical E/W bifacials have a “double hump” which provides more generation in the morning and evening, verticals take less floor space so you might be able to get extra panels or get panels at all, N/S bifacials have better winter production unless your slanted panels are “detuned” from perfect summer angle (or even better have a tilt mount you can update every few months, but that is not cheap).