When StrimziKafkaContainer was part of the public API, it was straightforward to customise the created container, ex. set up network or aliases, set labels for later identification, and inject env vars.

Now that StrimziKafkaContainer is removed, we cannot do all that.

Plus, the builder method withBootstrapServers introduced in 0.114.0 receives a function accepting StrimziKafkaContainer, which is no longer visible.

I can understand that StrimziKafkaContainer was retrieved from direct public use in order to focus on the single point of configuration which is the cluster.
But I think removing the visibility of the class makes this less useful.