Databricks Neon [1] has a free tier for their Postgres service. Neon's strength that allows them to offer a free tier lies in their serverless, cloud-native PostgreSQL architecture with a separation of storage and compute resources. This allows Neon to scale compute to zero automatically when the database is idle.
I’m not saying that can’t or doesn’t happen but I’ve been using them for about 2 years now and never experienced it. To be fair, my traffic patterns could just not overlap with their outages but wanted to add a data point.
[1] https://neon.com