There is no extra cost to have hot swappable unless you're considering buying consumer grade hardware, but consumer grade hardware is more expensive to host because it won't fit in 1U bays.
> Do you believe you're getting redundancy when you go with hetzner and a cheap desktop grade processor, ddr4 non ecc memory, and a consumer grade SSD?
Irrespective of how much I'd skimp on the hardware, I always have a HA setup, including on EC2, so it doesn't matter in any case.
Depending somewhat on the quality of the hardware in question. Hot swap capable isn't rare, but it's not going to happen at the bottom of the price continuum.
Not really, this is what RAID is for