Composer using old JSON for contrib module?
Im the maintainer of packages.drupal.org - I went ahead and deleted the invalid data out of the database, and this will install now.

I've also opened and issue on drupal.org to put more defensive measures in place. https://www.drupal.org/project/project_composer/issues/3076342

I think something must have changed in how permissive composer is with certain bad version constraints.