Revert "Merge branch '344807-frontend-api-requests-rate-limit-take2' into 'master'"

Reverting as !78082 (merged) caused gitlab-com/gl-infra/production#6207 (closed). The main change there was behind a feature flag but this method response type change wasn't, and some quite confusing existing method naming led to a subtle bug where we treated everything as a protected path 😞