Can you share some examples of high bandwidth 900 radios? In my experience, it’s difficult to get bitrates above ~100kbps on 900 over any meaningful distance.
I tried (and failed) to build a GoTenna competitor using LoRa and what you say here is 100% correct. Large scale mesh networks are incredibly difficult to build and often end up requiring extreme optimizations for specific use cases. We ultimately abandoned mesh networking in favor of a TDMA approach with base stations.
“smart home without the WiFi configuration” is exactly what Amazon’s network is for, but it won’t be anything more than that. The bandwidth and latencies required for content rich applications is simply not there. Sidewalk is cool enough without trying to sell the magic mesh network pipe dream.