When hardware planning last year, Analytics asked for budget to expand the 2 Kafka main clusters.
We planned to increase RAM to 64G (+32G) on each of the existent brokers, and add +2 brokers to each cluster. Analytics would like to put this task in SRE's backlog. The Kafka main clusters should be owned by SRE, so we want to leave it up to them to decide if and when this is needed.
AFAIK, the load on Kafka main is not planned to increase significantly in the near future.