I have my PR I mentioned above published to @illusionalsagacity/graphql-ppx@2.0.0-f885fc66.0 if you want a bridge to get to 11. We have been using this build without any issues since publication. If you run into version conflicts you can use the package.json overrides or yarn resolutions to fix that.
I have rescript 12 support in progress here and have it published under the rescript12 tag. I have not finished testing this yet, so while it seems to compile fine I’m not sure I would use it in prod just yet.