[Context: I worked with this team previously] Data here is coming from mobile apps, and is similar in volume to typical mobile app user analytics. I can certainly imagine that Segment would be a poor (or maybe just costly) fit for device telemetry in most IoT use-cases.
It hasn’t been an issue so far, but we have our own ingestion pipeline on our roadmap that will address this and other issues. (Renat from Kraftful team).