I think most web developers just do not understand SQL well enough to take advantage of these types of features (and if they do, they still may be sticking clos

I think most web developers just do not understand SQL well enough to take advantage of these types of features (and if they do, they still may be sticking closer to "standard" ANSI SQL, or may just not be up to date on newer features). Unfortunately, lots of web developers don't get past their ORM abstraction into what is occurring behind the scenes and how to make use of the full range of their database's features.