My "Homeserver" with its database running on an old laptop has less downtime than AWS.
I expect most, if not 99%, of all businesses can cope with a hardware failure and the associated downtime while restoring to a different server, judging from the impact of the recent AWS outage and the collective shrug in response. With a proper raid setup, data loss should be quite rare, if more is required a primary + secondary setup with a manual failover isn't hard.