Confluent has had a cloud offering for years now but made the self-serve options more available. Now the basic tier pricing has been changed to only be billed on data transferred instead of provisioned throughput. Kafka is the same between both services but Confluent provides extra like KSQL, Schema Registry and some of their other tools.
I've recently gotten quotes from Confluent Cloud after doing some pricing on AWS for our setup, and they are far more expensive than MSK, but you do get more bells and whistles. It's more cost-effective for us to run our own, which also gives us more flexibility when it comes to monitoring and alerting around the environment.
It isn’t as easy to do this for Kafka. Not only do they use the Apache License, as an Apache project they would need to completely change their governance. The ASF also owns the Apache trademark so Confluent would need to completely rebrand.
I wonder how it differs from the managed Kafka of Confluent since they also support AWS as the backend. It sounds like the same story of Elasticsearch, MongoDB and Redis though.
[1] https://www.confluent.io/confluent-cloud/