Our bikes have shimano hydraulic disks, textro mechanical disks, and various rim brakes. I would say the hydraulics are very good and can lock up the rear wheel, but my wife's 55 lb cruiser e-bike stops well with the mechanical disks.

My Trek 800 e-bike conversion had very weak center pull brakes. I changed out the pads and adjusted, but they were still unsafe. I converted to new v-brakes and it was far better, with stopping power that feels as good as the disk brake bikes.

My preference would be for disk brakes just because I like technology. A drawback with the hydraulic disks is that I will have to buy a bleeding kit this winter, and then I'll probably lose some pieces next year and have to buy a second one.