all the containers change IP addresses frequently. For home assistant a static IP address of the proxy manager is mandatory in order to reach it. For jellyfin it is useful to see which device accesses jellyfin. If the IP always changes, it doesn’t work properly.
How do I fix a container IP with podman compose (or docker)
It’s not as a fully scalable solution, no. Without swarm, last I checked, it cannot even really run on multiple instances. However, it does have the functionality to scale individual services within the same host if resources are available and the service can benefit from such a scaling. It is not very uncommon to see something require multiple worker instances and this breaks that paradigm.
Service discovery will certainly play a much larger role in even more orchestrated systems, but doesn’t mean it shouldn’t start here.