Pipeline job_activity_limit_exceeded for open source on gitlab.com

We (https://gitlab.com/coq/coq) regularly get the job limit error.

At https://docs.gitlab.com/ee/user/gitlab_com/index.html#gitlab-cicd it says "Max jobs in active pipelines 500 for Free tier, unlimited otherwise"

Are open source projects treated as the free plan? Usually they are treated as Gold plan AFAIK.