SPARQL is cool, but fairly limited. For example, one cannot implement common graph operations like a BFS or a DFS in SPARQL, and SQL of course can (even though I wouldn't necessarily recommend it). I was fairly puzzled when I figured this out. This means SQL is strictly more expressive than SPARQL!
The semweb badly needs a SPARQL 2.0 but we won’t get it, not least because the community was burnt out by the standards process. Myself I am keen on facilities common in document databases to represent ordered collections because the culmination of my work on the semantic web was figuring out how to use (mostly) OWL to represent complex document schemas such as the ISO 20022 financial messaging standard. And order matters for that!