SQL proficiency is something I've seen developers of all sorts neglect, which I think is a huge mistake. And relegating SQL to something that just an "analyst" does is an even bigger mistake.

Several times over my career I've been brought in on a project where the team was considering replacing their RDBMS entirely with a no-SQL data store (a huge undertaking!) because they were having "performance problems". In many cases the solution is as simple as adding an index or modifying a query to use an index, but the devs regard it as some kind of wizardry to read a query plan.