Yeah, I can agree with that. You'll get the most value out of understanding the 1 or 2 layers below. Digging all the way to bare metal is usually not necessary or practical, though it may help once in a long while.
For example, ORMs. If you try to use an ORM without knowing SQL you will have a bad time as soon as you hit performance issues or you have to do something that doesn't fit quite nicely into the ORM model. I have yet to see a project that uses an ORM that doesn't use SQL in places.
ORMs are not necessarily net positive. They make some things simpler at the cost of an extra layer of indirection.
Going a level deeper, knowing how query planners work at a high level will help writing performant SQL queries.
Going as far as understanding how your RDMS is implemented should not typically be necessary. It would help for finding bugs in the RDMS, but that should be very rare.
For example, ORMs. If you try to use an ORM without knowing SQL you will have a bad time as soon as you hit performance issues or you have to do something that doesn't fit quite nicely into the ORM model. I have yet to see a project that uses an ORM that doesn't use SQL in places.
ORMs are not necessarily net positive. They make some things simpler at the cost of an extra layer of indirection.
Going a level deeper, knowing how query planners work at a high level will help writing performant SQL queries.
Going as far as understanding how your RDMS is implemented should not typically be necessary. It would help for finding bugs in the RDMS, but that should be very rare.