Kafka is a log, not a queue. They have every so slightly different semantics, but logs have HOL blocking per partition for processing messages because they use a watermark, compared to queues, which track on a per-message basis.
The article already includes a couple of "not queues" that they use for event stream processing, Kinesis being one of them. Kinesis consumers also maintain a watermark to keep track of how far they've read in a stream. Considering that, a Kafka comparison seems like a reasonable ask.