Private repo host...because whatever they charge, it is cheaper than using an FTE to maintain it internally unless you want a flaky internal SLA.
I use it as a private repo host. The cost is a no-brainer. We'd probably pay 2x or 3x more compared to the value we're getting. The independence from the Cloud services (ECR, ACR, GCR) makes it a better option. Also, for now, there isnt any funny-math on multi-factor egress costs -- which become tricky to compute in real life.
We use it for containers to be run on k8s. As long as there are not super-low latency requirements for startup, I'd prefer an independent single private repo over multiple in-zone repos.