Greenspun's rule worked in favour of Common Lisp (to the extent that it did...) because CL solves a lot of hard problems that ad-hoc solutions do poorly, like automatic memory management, DSLs, etc.

But lots of apps can do with a lightweight pull API that can be tailored, fits the applications' access control model (as points of contrast to GraphQL) and it's less work and less risk than finding, integrating and betting on a GraphQL implementation.