Comment by hugofirth

You may be interested in https://www.gqlstandards.org/ and https://www.iso.org/standard/79473.html

TL;DR the ISO standards committees behind SQL are working on bring graph query languages and SQL databases closer together.

Obviously there is work to be done at the storage/query planning layer after that, but I’m hopeful once the surface exists more widely that will drive more work in those areas.