And that number might be high, in larger more established companies there might be more engineers who want to stick to their comfort bubble. So many developers reject the idea of writing SQL themselves instead of having the ORM do it, let alone know how to configure replication and failover.
I'd maybe hire for the people who could and would, but the people advocating for just having the cloud take care of these things have a point. You might miss out on an excellent application engineer, if you reject them for not having any Linux skills.