It made little difference, the entire ecosystem was highly unstable. Containers could still fail, the docker daemon could hang, and the host could kernel panic any minute. For databases that meant downtime and potential data corruption.

Besides, there is a major use case to run temporary databases for CI testing. I remember a lot of issues when running performance tests or seeding the database with initial data, basically anything that is performance intensive. I think the unstable filesystem played a role but it was far from the only root cause.

Honestly it's been 6 years now and I've never seen a company running any critical databases inside docker (but I've seen it for testing). I've known a lot of companies that said they did or they had plans to move existing databases, but that wasn't real. At the end of the day there was no sysadmin/DBA/devops who would do it, they understood that it would come back to bite them (many had enough troubles just running ephemeral web services). Maybe it's the harder part to grasp but database is really a different mindset from web development, you cannot risk losing customer data, this would be an extinction level event for your job and for the company.