Most MQTT brokers are not great at storing data. The pattern that works the best for me in solving the "edge delivery" use case is a lightweight clustered MQTT

Most MQTT brokers are not great at storing data. The pattern that works the best for me in solving the "edge delivery" use case is a lightweight clustered MQTT broker (e.g. VerneMQ) with a little Lua script inside to push everything into Redis Streams (of course, clustered as well) immediately. Kafka is another alternative, but it's not that lightweight, operationally, and often Redis Streams are "good enough". With an LB in front of both Verne and Redis, this setup is pretty decent for IoT data ingress.