It's not a superpower at all--instead, I'd argue that it's the most important skillset (after understanding the relational model itself) for interacting with RD

It's not a superpower at all--instead, I'd argue that it's the most important skillset (after understanding the relational model itself) for interacting with RDBMSes at scale. You don't necessarily have to know whether an index scan is going to be parallelized or whether the CBO is going to switch to a loop because its heuristics think your result set is likely tiny to think about things like "is this data being accessed via the right indexes? Is the data likely in memory or not? Will my joins, given my consistency level, impose locks or concurrency considerations on the tables I expect?"